Air events
822 causally classified PM2.5 events across the 100 largest US metros. Each is resolved to a root cause through retained evidence—official assessments, agency statements, news coverage, or NOAA records—or a clearly disclosed lower-confidence inference. The 425 remaining local episodes stay with their city records; they are not presented here as causal or regional events.
57.7 µg/m³ peak ≈ 4.5 cigarettes per person 846k people affected
Wildfire smoke over Boise City, 2 days, peaking at 57.7 µg/m³ near Boise City.
NWS alert 1Agency/press 1
51.5 µg/m³ peak ≈ 1.8 cigarettes per person 2.8M people affected
Wildfire smoke over St. Louis, 1 day, peaking at 51.5 µg/m³ near St. Louis.
130.6 µg/m³ peak ≈ 5.6 cigarettes per person 605k people affected
Wildfire smoke over Spokane, 1 day, peaking at 130.6 µg/m³ near Spokane.
Origin: Canada; Northern Minnesota
387.8 µg/m³ peak ≈ 13.0 cigarettes per person 86M people affected 14 city records set, 27 top-ten days
Wildfire smoke over 32 metros, 6 days, peaking at 387.8 µg/m³ near Toledo. 14 metros set an all-time record. Origin traced to Canada; Northern Minnesota.
EPA AQS 1NWS alert 6Agency/press 6gdelt-doc-api 1
30.5 µg/m³ peak ≈ 1.1 cigarettes per person 1.1M people affected 1 top-ten day
Dust over Tucson, 1 day, peaking at 30.5 µg/m³ near Tucson.
Reviewed source 1gdelt-doc-api 2
54.7 µg/m³ peak ≈ 2.0 cigarettes per person 6.4M people affected
Fireworks over Washington, 1 day, peaking at 54.7 µg/m³ near Washington.
51 µg/m³ peak ≈ 1.9 cigarettes per person 6.5M people affected 1 top-ten day
Fireworks over Miami, 1 day, peaking at 51 µg/m³ near Miami.
72.1 µg/m³ peak ≈ 2.6 cigarettes per person 4.0M people affected 1 city record set, 2 top-ten days
Fireworks over 3 metros, 2 days, peaking at 72.1 µg/m³ near Omaha. 1 metro set an all-time record.
Agency/press 2 4
25.8 µg/m³ peak ≈ 0.9 cigarettes per person 778k people affected
Wildfire smoke over Colorado Springs, 1 day, peaking at 25.8 µg/m³ near Colorado Springs.
Named source South Canal Fire
64.9 µg/m³ peak ≈ 2.6 cigarettes per person 1.8M people affected 1 top-ten day
Wildfire smoke over Jacksonville, 1 day, peaking at 64.9 µg/m³ near Jacksonville.
Agency/press 1
44.1 µg/m³ peak ≈ 1.6 cigarettes per person 915k people affected
Prescribed fire over McAllen, 1 day, peaking at 44.1 µg/m³ near McAllen.
36.1 µg/m³ peak ≈ 1.2 cigarettes per person 2.6M people affected
Prescribed fire over Austin, 1 day, peaking at 36.1 µg/m³ near Austin.
Agency/press 1Reviewed source 1
30.3 µg/m³ peak ≈ 1.1 cigarettes per person 1.1M people affected 1 top-ten day
Dust over Tucson, 1 day, peaking at 30.3 µg/m³ near Tucson.
43.8 µg/m³ peak ≈ 1.5 cigarettes per person 588k people affected
Prescribed fire over Chattanooga, 1 day, peaking at 43.8 µg/m³ near Chattanooga.
50.2 µg/m³ peak ≈ 1.8 cigarettes per person 637k people affected 1 top-ten day
Mixed causes over Augusta, 1 day, peaking at 50.2 µg/m³ near Augusta.
EPA AQS 2
46.4 µg/m³ peak ≈ 1.7 cigarettes per person 661k people affected
Prescribed fire over Wichita, 1 day, peaking at 46.4 µg/m³ near Wichita.
35.8 µg/m³ peak ≈ 1.2 cigarettes per person 606k people affected
Prescribed fire over Jackson, 1 day, peaking at 35.8 µg/m³ near Jackson.
EPA AQS 1internet-archive-wayback-cdx 1
43.9 µg/m³ peak ≈ 1.6 cigarettes per person 915k people affected
Other over McAllen, 1 day, peaking at 43.9 µg/m³ near McAllen.
Agency/press 2
Origin: Vegetation burning in Mexico
35.2 µg/m³ peak ≈ 1.2 cigarettes per person 2.8M people affected
Prescribed fire over San Antonio, 1 day, peaking at 35.2 µg/m³ near San Antonio. Origin traced to Vegetation burning in Mexico.
Reviewed source 3
54.5 µg/m³ peak ≈ 2.1 cigarettes per person 661k people affected 1 top-ten day
Mixed causes over Wichita, 1 day, peaking at 54.5 µg/m³ near Wichita.
EPA AQS 1News 1gdelt-doc-api 2
36.7 µg/m³ peak ≈ 1.3 cigarettes per person 740k people affected 1 top-ten day
Wildfire smoke over Deltona, 1 day, peaking at 36.7 µg/m³ near Deltona.
110.1 µg/m³ peak ≈ 4.6 cigarettes per person 870k people affected 1 city record set
Wildfire smoke over Charleston, 1 day, peaking at 110.1 µg/m³ near Charleston. 1 metro set an all-time record.
33.9 µg/m³ peak ≈ 1.2 cigarettes per person 2.9M people affected
Prescribed fire over Orlando, 1 day, peaking at 33.9 µg/m³ near Orlando.
News 1gdelt-doc-api 1
48.5 µg/m³ peak ≈ 1.7 cigarettes per person 637k people affected 1 top-ten day
Mixed causes over Augusta, 1 day, peaking at 48.5 µg/m³ near Augusta.
EPA AQS 2
85 µg/m³ peak ≈ 3.3 cigarettes per person 7.8M people affected 1 top-ten day
Fireworks over Houston, 1 day, peaking at 85 µg/m³ near Houston.
67.8 µg/m³ peak ≈ 2.7 cigarettes per person 2.8M people affected 1 top-ten day
Fireworks over San Antonio, 1 day, peaking at 67.8 µg/m³ near San Antonio.
Reviewed source 1gdelt-doc-api 1
57.8 µg/m³ peak ≈ 1.9 cigarettes per person 4.3M people affected 1 top-ten day
Fireworks over 2 metros, 1 day, peaking at 57.8 µg/m³ near Tampa.
44.4 µg/m³ peak ≈ 1.5 cigarettes per person 637k people affected
Prescribed fire over Augusta, 1 day, peaking at 44.4 µg/m³ near Augusta.
168.1 µg/m³ peak ≈ 17.5 cigarettes per person 605k people affected 1 top-ten day
Wildfire smoke over Spokane, 3 days, peaking at 168.1 µg/m³ near Spokane.
45.9 µg/m³ peak ≈ 1.7 cigarettes per person 1.6M people affected
Wildfire smoke over 2 metros, 1 day, peaking at 45.9 µg/m³ near Hartford.
EPA AQS 1Agency/press 1
Origin: Canada
51.5 µg/m³ peak ≈ 6.1 cigarettes per person 3.8M people affected 3 top-ten days
Wildfire smoke over 4 metros, 5 days, peaking at 51.5 µg/m³ near Buffalo. Origin traced to Canada.
Agency/press 1
Origin: Canada
89.8 µg/m³ peak ≈ 4.0 cigarettes per person 29M people affected 8 top-ten days
Wildfire smoke over 11 metros, 7 days, peaking at 89.8 µg/m³ near Milwaukee. Origin traced to Canada.
EPA AQS 18NWS alert 4Agency/press 7internet-archive-wayback-cdx 1
49.7 µg/m³ peak ≈ 2.5 cigarettes per person 1.9M people affected 1 top-ten day
Wildfire smoke over 2 metros, 2 days, peaking at 49.7 µg/m³ near Albany.
Reviewed source 2News 1gdelt-doc-api 2
51.1 µg/m³ peak ≈ 1.9 cigarettes per person 3.8M people affected
Wildfire smoke over Minneapolis, 1 day, peaking at 51.1 µg/m³ near Minneapolis.
EPA AQS 1Agency/press 1
49.6 µg/m³ peak ≈ 1.8 cigarettes per person 601k people affected
Wildfire smoke over Toledo, 1 day, peaking at 49.6 µg/m³ near Toledo.
Origin: Central Canada
89.8 µg/m³ peak ≈ 4.6 cigarettes per person 5.3M people affected 1 top-ten day
Wildfire smoke over 2 metros, 2 days, peaking at 89.8 µg/m³ near Minneapolis. Origin traced to Central Canada.
EPA AQS 3NWS alert 1Agency/press 3
59 µg/m³ peak ≈ 2.2 cigarettes per person 6.4M people affected
Fireworks over Washington, 1 day, peaking at 59 µg/m³ near Washington.
82.1 µg/m³ peak ≈ 3.6 cigarettes per person 6.7M people affected 3 top-ten days
Fireworks over 4 metros, 2 days, peaking at 82.1 µg/m³ near Indianapolis.
EPA AQS 4News 1gdelt-doc-api 2
38 µg/m³ peak ≈ 1.4 cigarettes per person 926k people affected
Fireworks over Albuquerque, 1 day, peaking at 38 µg/m³ near Albuquerque.
69.2 µg/m³ peak ≈ 2.5 cigarettes per person 6.3M people affected
Wildfire smoke over Philadelphia, 1 day, peaking at 69.2 µg/m³ near Philadelphia.
49.4 µg/m³ peak ≈ 2.7 cigarettes per person 1.7M people affected 1 top-ten day
Wildfire smoke over 2 metros, 2 days, peaking at 49.4 µg/m³ near Rochester.
News 1gdelt-doc-api 3
Origin: Canada
93.5 µg/m³ peak ≈ 2.4 cigarettes per person 20M people affected 2 top-ten days
Wildfire smoke over 6 metros, 4 days, peaking at 93.5 µg/m³ near Minneapolis. Origin traced to Canada.
EPA AQS 8NWS alert 1Agency/press 3
78.5 µg/m³ peak ≈ 6.0 cigarettes per person 879k people affected
Dust over El Paso, 2 days, peaking at 78.5 µg/m³ near El Paso.
Origin: Regional windblown dust affecting El Paso
164.3 µg/m³ peak ≈ 7.0 cigarettes per person 879k people affected 1 top-ten day
Dust over El Paso, 1 day, peaking at 164.3 µg/m³ near El Paso. Origin traced to Regional windblown dust affecting El Paso.
Reviewed source 2News 1gdelt-doc-api 2
Origin: Windblown regional desert dust
107.2 µg/m³ peak ≈ 8.7 cigarettes per person 879k people affected 1 top-ten day
Dust over El Paso, 2 days, peaking at 107.2 µg/m³ near El Paso. Origin traced to Windblown regional desert dust.
NOAA 1NWS record 1Reviewed source 2gdelt-doc-api 1
Origin: Windblown regional desert dust
288.5 µg/m³ peak ≈ 12.7 cigarettes per person 879k people affected 1 city record set
Dust over El Paso, 1 day, peaking at 288.5 µg/m³ near El Paso. 1 metro set an all-time record. Origin traced to Windblown regional desert dust.
NWS record 1Agency/press 1Reviewed source 2
51.7 µg/m³ peak ≈ 3.7 cigarettes per person 588k people affected 1 top-ten day
Prescribed fire over Chattanooga, 2 days, peaking at 51.7 µg/m³ near Chattanooga.
39 µg/m³ peak ≈ 1.4 cigarettes per person 661k people affected
Prescribed fire over Wichita, 1 day, peaking at 39 µg/m³ near Wichita.
Origin: El Paso Borderland
285.8 µg/m³ peak ≈ 12.6 cigarettes per person 879k people affected 1 top-ten day
Dust over El Paso, 1 day, peaking at 285.8 µg/m³ near El Paso. Origin traced to El Paso Borderland.
NWS record 2Agency/press 2 1
75.5 µg/m³ peak ≈ 2.8 cigarettes per person 2.8M people affected 1 top-ten day
Dust over St. Louis, 1 day, peaking at 75.5 µg/m³ near St. Louis.
Origin: Oklahoma and eastern Kansas fires; Southwestern United States dust
72.4 µg/m³ peak ≈ 2.3 cigarettes per person 3.2M people affected 1 city record set, 2 top-ten days
Mixed causes over 3 metros, 1 day, peaking at 72.4 µg/m³ near Tulsa. 1 metro set an all-time record. Origin traced to Oklahoma and eastern Kansas fires; Southwestern United States dust.
EPA AQS 2NWS record 1Agency/press 2
Origin: March 14 North Texas windblown-dust outbreak
72.3 µg/m³ peak ≈ 3.7 cigarettes per person 11M people affected 1 city record set
Mixed causes over 2 metros, 2 days, peaking at 72.3 µg/m³ near Dallas. 1 metro set an all-time record. Origin traced to March 14 North Texas windblown-dust outbreak.
Reviewed source 5Agency/press 2
Origin: Southwestern United States; Texas and Oklahoma Panhandles
64.7 µg/m³ peak ≈ 2.3 cigarettes per person 3.0M people affected 1 city record set, 2 top-ten days
Dust over 2 metros, 2 days, peaking at 64.7 µg/m³ near Kansas City. 1 metro set an all-time record. Origin traced to Southwestern United States; Texas and Oklahoma Panhandles.
EPA AQS 1Agency/press 4internet-archive-wayback-cdx 2
60.5 µg/m³ peak ≈ 2.3 cigarettes per person 879k people affected
Dust over El Paso, 1 day, peaking at 60.5 µg/m³ near El Paso.
Agency/press 1gdelt-doc-api 1
97.8 µg/m³ peak ≈ 6.2 cigarettes per person 588k people affected 1 top-ten day
Mixed causes over Chattanooga, 2 days, peaking at 97.8 µg/m³ near Chattanooga.
EPA AQS 3gdelt-doc-api 1
127.3 µg/m³ peak ≈ 5.4 cigarettes per person 879k people affected 1 top-ten day
Dust over El Paso, 1 day, peaking at 127.3 µg/m³ near El Paso.
NOAA 1NWS record 1Reviewed source 1gdelt-doc-api 2
238.6 µg/m³ peak ≈ 15.7 cigarettes per person 879k people affected 1 top-ten day
Dust over El Paso, 2 days, peaking at 238.6 µg/m³ near El Paso.
59.2 µg/m³ peak ≈ 2.3 cigarettes per person 879k people affected
Dust over El Paso, 1 day, peaking at 59.2 µg/m³ near El Paso.
Agency/press 1gdelt-doc-api 6
47.2 µg/m³ peak ≈ 1.7 cigarettes per person 637k people affected 1 top-ten day
Prescribed fire over Augusta, 1 day, peaking at 47.2 µg/m³ near Augusta.
EPA AQS 1NWS alert 1gdelt-doc-api 1
63.3 µg/m³ peak ≈ 2.4 cigarettes per person 879k people affected
Dust over El Paso, 1 day, peaking at 63.3 µg/m³ near El Paso.
94.2 µg/m³ peak ≈ 8.9 cigarettes per person 879k people affected 1 top-ten day
Dust over El Paso, 3 days, peaking at 94.2 µg/m³ near El Paso.
Reviewed source 1Agency/press 1
Named source Hughes Fire
45.3 µg/m³ peak ≈ 1.6 cigarettes per person 835k people affected
Wildfire smoke over Oxnard, 1 day, peaking at 45.3 µg/m³ near Oxnard.
EPA AQS 1NWS alert 1Agency/press 2
Cited: Ventura County Air Pollution Control District
23.5 µg/m³ peak ≈ 0.8 cigarettes per person 861k people affected
Prescribed fire over Cape Coral, 1 day, peaking at 23.5 µg/m³ near Cape Coral.
Reviewed source 5
31 µg/m³ peak ≈ 1.1 cigarettes per person 1.1M people affected 1 top-ten day
Dust over Tucson, 1 day, peaking at 31 µg/m³ near Tucson.
59.2 µg/m³ peak ≈ 2.1 cigarettes per person 3.3M people affected
Fireworks over San Diego, 1 day, peaking at 59.2 µg/m³ near San Diego.
210.3 µg/m³ peak ≈ 9.8 cigarettes per person 6.3M people affected 1 city record set
Fireworks over 2 metros, 2 days, peaking at 210.3 µg/m³ near Phoenix. 1 metro set an all-time record.
EPA AQS 3Agency/press 2
50.7 µg/m³ peak ≈ 1.7 cigarettes per person 2.2M people affected
Wildfire smoke over Indianapolis, 1 day, peaking at 50.7 µg/m³ near Indianapolis.
43.3 µg/m³ peak ≈ 1.5 cigarettes per person 769k people affected 1 top-ten day
Dust over Little Rock, 1 day, peaking at 43.3 µg/m³ near Little Rock.
Origin: Southern California
85.9 µg/m³ peak ≈ 3.2 cigarettes per person 7.1M people affected 1 top-ten day
Wildfire smoke over 2 metros, 3 days, peaking at 85.9 µg/m³ near Riverside. Origin traced to Southern California.
EPA AQS 2NWS alert 1Agency/press 2
89.5 µg/m³ peak ≈ 6.7 cigarettes per person 846k people affected 1 city record set
Wildfire smoke over Boise City, 2 days, peaking at 89.5 µg/m³ near Boise City. 1 metro set an all-time record.
EPA AQS 4NWS alert 1Agency/press 1
Named source Bogus Basin Road vegetation fire
64.7 µg/m³ peak ≈ 2.6 cigarettes per person 846k people affected 1 top-ten day
Wildfire smoke over Boise City, 1 day, peaking at 64.7 µg/m³ near Boise City.
EPA AQS 2NWS alert 1Agency/press 1
46.2 µg/m³ peak ≈ 1.5 cigarettes per person 2.1M people affected 1 top-ten day
Mixed causes over 2 metros, 1 day, peaking at 46.2 µg/m³ near Memphis.
EPA AQS 2News 1
35.5 µg/m³ peak ≈ 1.2 cigarettes per person 1.5M people affected
Wildfire smoke over Oklahoma City, 1 day, peaking at 35.5 µg/m³ near Oklahoma City.
Reviewed source 1News 1
38.7 µg/m³ peak ≈ 1.3 cigarettes per person 5.3M people affected
Dust over 2 metros, 1 day, peaking at 38.7 µg/m³ near San Antonio.
EPA AQS 2Agency/press 1
60.1 µg/m³ peak ≈ 2.4 cigarettes per person 846k people affected
Wildfire smoke over Boise City, 1 day, peaking at 60.1 µg/m³ near Boise City.
EPA AQS 2NWS alert 1
Origin: eastern Oregon
89.1 µg/m³ peak ≈ 3.7 cigarettes per person 846k people affected 1 top-ten day
Wildfire smoke over Boise City, 1 day, peaking at 89.1 µg/m³ near Boise City. Origin traced to eastern Oregon.
EPA AQS 2NWS alert 1Agency/press 1
Origin: Canada
29.7 µg/m³ peak ≈ 2.1 cigarettes per person 778k people affected
Wildfire smoke over Colorado Springs, 2 days, peaking at 29.7 µg/m³ near Colorado Springs. Origin traced to Canada.
NWS alert 1Agency/press 1
64 µg/m³ peak ≈ 2.4 cigarettes per person 4.4M people affected
Fireworks over Detroit, 1 day, peaking at 64 µg/m³ near Detroit.
EPA AQS 1Agency/press 1
43.9 µg/m³ peak ≈ 1.6 cigarettes per person 2.4M people affected
Fireworks over Las Vegas, 1 day, peaking at 43.9 µg/m³ near Las Vegas.
EPA AQS 1Agency/press 1
27.2 µg/m³ peak ≈ 1.0 cigarettes per person 1.1M people affected
Dust over Tucson, 1 day, peaking at 27.2 µg/m³ near Tucson.
NWS alert 1News 1gdelt-doc-api 1
Origin: Arizona; New Mexico
39 µg/m³ peak ≈ 1.4 cigarettes per person 2.4M people affected
Wildfire smoke over Las Vegas, 1 day, peaking at 39 µg/m³ near Las Vegas. Origin traced to Arizona; New Mexico.
EPA AQS 1Agency/press 1
Cited: Clark County
Origin: Central America; Mexico
63.8 µg/m³ peak ≈ 2.7 cigarettes per person 3.7M people affected 1 top-ten day
Wildfire smoke over 2 metros, 4 days, peaking at 63.8 µg/m³ near McAllen. Origin traced to Central America; Mexico.
EPA AQS 4Agency/press 1
Origin: Central America; Mexico
57.7 µg/m³ peak ≈ 3.2 cigarettes per person 22M people affected 3 top-ten days
Wildfire smoke over 5 metros, 9 days, peaking at 57.7 µg/m³ near McAllen. Origin traced to Central America; Mexico.
EPA AQS 20Agency/press 2
Origin: Central America; Mexico
51.4 µg/m³ peak ≈ 1.9 cigarettes per person 915k people affected
Wildfire smoke over McAllen, 1 day, peaking at 51.4 µg/m³ near McAllen. Origin traced to Central America; Mexico.
EPA AQS 1Agency/press 1
Origin: northeast British Columbia
56.5 µg/m³ peak ≈ 2.1 cigarettes per person 3.8M people affected
Wildfire smoke over Minneapolis, 1 day, peaking at 56.5 µg/m³ near Minneapolis. Origin traced to northeast British Columbia.
EPA AQS 1Agency/press 1
Cited: Minnesota Pollution Control Agency
Origin: Central America; Mexico
55.7 µg/m³ peak ≈ 2.4 cigarettes per person 14M people affected 3 top-ten days
Wildfire smoke over 4 metros, 3 days, peaking at 55.7 µg/m³ near McAllen. Origin traced to Central America; Mexico.
EPA AQS 7Agency/press 2
38.2 µg/m³ peak ≈ 1.4 cigarettes per person 661k people affected
Other over Wichita, 1 day, peaking at 38.2 µg/m³ near Wichita.
Agency/press 1
Cited: Kansas Department of Health and Environment
120.1 µg/m³ peak ≈ 3.2 cigarettes per person 1.7M people affected 1 city record set
Prescribed fire over 2 metros, 2 days, peaking at 120.1 µg/m³ near Wichita. 1 metro set an all-time record.
EPA AQS 2Agency/press 2
Cited: Kansas Department of Health and Environment
Origin: Central America; Mexico
36.1 µg/m³ peak ≈ 1.2 cigarettes per person 5.3M people affected
Wildfire smoke over 2 metros, 1 day, peaking at 36.1 µg/m³ near San Antonio. Origin traced to Central America; Mexico.
EPA AQS 2
39.4 µg/m³ peak ≈ 1.3 cigarettes per person 1.1M people affected 1 top-ten day
Other over Tulsa, 1 day, peaking at 39.4 µg/m³ near Tulsa.
Agency/press 1
Cited: Kansas Department of Health and Environment
51.6 µg/m³ peak ≈ 1.9 cigarettes per person 870k people affected 1 top-ten day
Prescribed fire over Columbia, 1 day, peaking at 51.6 µg/m³ near Columbia.
EPA AQS 1NWS alert 1Agency/press 1
39.1 µg/m³ peak ≈ 1.3 cigarettes per person 2.3M people affected
Prescribed fire over Kansas City, 1 day, peaking at 39.1 µg/m³ near Kansas City.
54.9 µg/m³ peak ≈ 2.2 cigarettes per person 846k people affected
Winter inversion over Boise City, 1 day, peaking at 54.9 µg/m³ near Boise City.
Agency/press 1
108.2 µg/m³ peak ≈ 4.5 cigarettes per person 966k people affected 1 city record set
Mixed causes over New Orleans, 1 day, peaking at 108.2 µg/m³ near New Orleans. 1 metro set an all-time record.
103.1 µg/m³ peak ≈ 4.1 cigarettes per person 7.8M people affected 1 top-ten day
Fireworks over Houston, 1 day, peaking at 103.1 µg/m³ near Houston.
Agency/press 1
102.8 µg/m³ peak ≈ 3.6 cigarettes per person 6.3M people affected 1 top-ten day
Mixed causes over 2 metros, 1 day, peaking at 102.8 µg/m³ near Phoenix.
EPA AQS 2Agency/press 1
47.9 µg/m³ peak ≈ 1.8 cigarettes per person 3.4M people affected 1 top-ten day
Fireworks over Tampa, 1 day, peaking at 47.9 µg/m³ near Tampa.
27.4 µg/m³ peak ≈ 1.0 cigarettes per person 999k people affected
Fireworks over Urban Honolulu, 1 day, peaking at 27.4 µg/m³ near Urban Honolulu.
64 µg/m³ peak ≈ 3.1 cigarettes per person 10M people affected 3 top-ten days
Fireworks over 3 metros, 2 days, peaking at 64 µg/m³ near Miami.
95.2 µg/m³ peak ≈ 3.8 cigarettes per person 5.2M people affected
Residential combustion over Phoenix, 1 day, peaking at 95.2 µg/m³ near Phoenix.
Agency/press 1Reviewed source 1
Origin: Canada
50.7 µg/m³ peak ≈ 1.7 cigarettes per person 2.2M people affected
Wildfire smoke over Indianapolis, 1 day, peaking at 50.7 µg/m³ near Indianapolis. Origin traced to Canada.
EPA AQS 2
Origin: Canada
47.9 µg/m³ peak ≈ 1.6 cigarettes per person 17M people affected 1 city record set, 4 top-ten days
Wildfire smoke over 8 metros, 4 days, peaking at 47.9 µg/m³ near North Port. 1 metro set an all-time record. Origin traced to Canada.
EPA AQS 10Agency/press 4
Origin: Canada
63.4 µg/m³ peak ≈ 3.3 cigarettes per person 4.7M people affected 3 top-ten days
Wildfire smoke over 4 metros, 2 days, peaking at 63.4 µg/m³ near Wichita. Origin traced to Canada.
EPA AQS 6NWS alert 1Agency/press 5internet-archive-wayback-cdx 1
Named source Gray Fire, Ridge Creek Fire, Oregon Road Fire · Canada
239.7 µg/m³ peak ≈ 5.4 cigarettes per person 4.8M people affected 1 top-ten day
Wildfire smoke over 2 metros, 2 days, peaking at 239.7 µg/m³ near Spokane. Origin traced to Canada.
EPA AQS 3NWS alert 1Agency/press 3
Origin: Canada
59.1 µg/m³ peak ≈ 1.9 cigarettes per person 3.5M people affected 1 top-ten day
Wildfire smoke over 3 metros, 2 days, peaking at 59.1 µg/m³ near Madison. Origin traced to Canada.
EPA AQS 4Agency/press 2News 1gdelt-doc-api 3
Origin: Canada
67.2 µg/m³ peak ≈ 2.2 cigarettes per person 32M people affected 10 top-ten days
Wildfire smoke over 18 metros, 4 days, peaking at 67.2 µg/m³ near Des Moines. Origin traced to Canada.
EPA AQS 25NWS alert 2Agency/press 7News 1gdelt-doc-api 5
Origin: Seattle-Tacoma-Bellevue, WA
118.2 µg/m³ peak ≈ 5.0 cigarettes per person 4.1M people affected 1 top-ten day
Fireworks over Seattle, 1 day, peaking at 118.2 µg/m³ near Seattle. Origin traced to Seattle-Tacoma-Bellevue, WA.
76.8 µg/m³ peak ≈ 7.2 cigarettes per person 754k people affected 1 top-ten day
Wildfire smoke over Des Moines, 3 days, peaking at 76.8 µg/m³ near Des Moines.
Origin: Canada
210.1 µg/m³ peak ≈ 7.6 cigarettes per person 97M people affected 4 city records set, 33 top-ten days
Wildfire smoke over 42 metros, 6 days, peaking at 210.1 µg/m³ near Cleveland. 4 metros set an all-time record. Origin traced to Canada.
EPA AQS 124NWS alert 5Agency/press 6News 1gdelt-doc-api 2
Origin: Canada
111.3 µg/m³ peak ≈ 4.1 cigarettes per person 4.5M people affected 1 top-ten day
Wildfire smoke over 2 metros, 1 day, peaking at 111.3 µg/m³ near Minneapolis. Origin traced to Canada.
Origin: Mexico and Central America
34.8 µg/m³ peak ≈ 1.2 cigarettes per person 2.6M people affected
Wildfire smoke over Austin, 1 day, peaking at 34.8 µg/m³ near Austin. Origin traced to Mexico and Central America.
EPA AQS 1gdelt-doc-api 1
Origin: Canada
258.9 µg/m³ peak ≈ 11.3 cigarettes per person 63M people affected 12 city records set, 20 top-ten days
Wildfire smoke over 25 metros, 6 days, peaking at 258.9 µg/m³ near Allentown. 12 metros set an all-time record. Origin traced to Canada.
EPA AQS 59NWS alert 2Agency/press 7News 1gdelt-doc-api 5
Origin: Canada
95.6 µg/m³ peak ≈ 3.9 cigarettes per person 8.6M people affected 2 city records set
Wildfire smoke over 4 metros, 3 days, peaking at 95.6 µg/m³ near Denver. 2 metros set an all-time record. Origin traced to Canada.
EPA AQS 6NWS alert 1Agency/press 4
39 µg/m³ peak ≈ 1.3 cigarettes per person 1.1M people affected 1 top-ten day
Mixed causes over Tulsa, 1 day, peaking at 39 µg/m³ near Tulsa.
Origin: Houston-The Woodlands-Sugar Land, TX
43.8 µg/m³ peak ≈ 1.4 cigarettes per person 7.8M people affected
Prescribed fire over Houston, 1 day, peaking at 43.8 µg/m³ near Houston. Origin traced to Houston-The Woodlands-Sugar Land, TX.
News 1gdelt-doc-api 1
44.6 µg/m³ peak ≈ 1.6 cigarettes per person 870k people affected 1 top-ten day
Wildfire smoke over Columbia, 1 day, peaking at 44.6 µg/m³ near Columbia.
Origin: Jackson, MS
37.6 µg/m³ peak ≈ 1.2 cigarettes per person 606k people affected
Prescribed fire over Jackson, 1 day, peaking at 37.6 µg/m³ near Jackson. Origin traced to Jackson, MS.
EPA AQS 1internet-archive-wayback-cdx 3gdelt-doc-api 1
45.2 µg/m³ peak ≈ 1.6 cigarettes per person 8.3M people affected
Mixed causes over Dallas, 1 day, peaking at 45.2 µg/m³ near Dallas.
EPA AQS 1News 1gdelt-doc-api 1
Origin: Minneapolis-St. Paul-Bloomington, MN-WI
64.4 µg/m³ peak ≈ 2.5 cigarettes per person 3.8M people affected
Winter inversion over Minneapolis, 1 day, peaking at 64.4 µg/m³ near Minneapolis. Origin traced to Minneapolis-St. Paul-Bloomington, MN-WI.
Origin: New Orleans-Metairie, LA
45.5 µg/m³ peak ≈ 1.6 cigarettes per person 966k people affected 1 top-ten day
Fireworks over New Orleans, 1 day, peaking at 45.5 µg/m³ near New Orleans. Origin traced to New Orleans-Metairie, LA.
Origin: Austin-Round Rock, TX; San Antonio-New Braunfels, TX
44.1 µg/m³ peak ≈ 1.5 cigarettes per person 5.3M people affected 1 top-ten day
Fireworks over 2 metros, 1 day, peaking at 44.1 µg/m³ near Austin. Origin traced to Austin-Round Rock, TX; San Antonio-New Braunfels, TX.
EPA AQS 1gdelt-doc-api 1
Origin: Urban Honolulu, HI
42 µg/m³ peak ≈ 1.7 cigarettes per person 999k people affected
Fireworks over Urban Honolulu, 1 day, peaking at 42 µg/m³ near Urban Honolulu. Origin traced to Urban Honolulu, HI.
Origin: Miami-Fort Lauderdale-West Palm Beach, FL
37.1 µg/m³ peak ≈ 1.3 cigarettes per person 6.5M people affected
Fireworks over Miami, 1 day, peaking at 37.1 µg/m³ near Miami. Origin traced to Miami-Fort Lauderdale-West Palm Beach, FL.
68.4 µg/m³ peak ≈ 2.3 cigarettes per person 6.3M people affected
Fireworks over 2 metros, 2 days, peaking at 68.4 µg/m³ near Phoenix.
EPA AQS 2Agency/press 3
62.7 µg/m³ peak ≈ 2.3 cigarettes per person 5.2M people affected
Residential combustion over Phoenix, 1 day, peaking at 62.7 µg/m³ near Phoenix.
Reviewed source 2Agency/press 1
59.7 µg/m³ peak ≈ 2.1 cigarettes per person 2.2M people affected 1 top-ten day
Temperature inversion over Indianapolis, 1 day, peaking at 59.7 µg/m³ near Indianapolis.
Reviewed source 3gdelt-doc-api 1
Named source Nakia Creek Fire · Oregon; Washington
255.9 µg/m³ peak ≈ 17.7 cigarettes per person 6.7M people affected 1 city record set, 2 top-ten days
Wildfire smoke over 2 metros, 9 days, peaking at 255.9 µg/m³ near Seattle. 1 metro set an all-time record. Origin traced to Oregon; Washington.
EPA AQS 6Agency/press 5
66.5 µg/m³ peak ≈ 2.6 cigarettes per person 4.1M people affected
Wildfire smoke over Seattle, 1 day, peaking at 66.5 µg/m³ near Seattle.
EPA AQS 1NWS alert 1Agency/press 2
103.5 µg/m³ peak ≈ 4.4 cigarettes per person 605k people affected
Wildfire smoke over Spokane, 1 day, peaking at 103.5 µg/m³ near Spokane.
EPA AQS 1NWS alert 1Agency/press 2
67.7 µg/m³ peak ≈ 2.7 cigarettes per person 4.1M people affected
Wildfire smoke over Seattle, 1 day, peaking at 67.7 µg/m³ near Seattle.
EPA AQS 1NWS alert 1Agency/press 1
60.6 µg/m³ peak ≈ 2.4 cigarettes per person 846k people affected
Wildfire smoke over Boise City, 1 day, peaking at 60.6 µg/m³ near Boise City.
EPA AQS 2NWS alert 1Agency/press 1
59.5 µg/m³ peak ≈ 4.2 cigarettes per person 2.4M people affected 1 top-ten day
Dust over Las Vegas, 2 days, peaking at 59.5 µg/m³ near Las Vegas.
EPA AQS 2Agency/press 1
46.2 µg/m³ peak ≈ 1.7 cigarettes per person 1.2M people affected
Fireworks over Buffalo, 1 day, peaking at 46.2 µg/m³ near Buffalo.
EPA AQS 1gdelt-doc-api 1
22.5 µg/m³ peak ≈ 1.5 cigarettes per person 658k people affected
Dust over Palm Bay, 2 days, peaking at 22.5 µg/m³ near Palm Bay.
Reviewed source 1Agency/press 1
Origin: June 2022 Saharan dust plume
21.2 µg/m³ peak ≈ 0.7 cigarettes per person 861k people affected
Dust over Cape Coral, 1 day, peaking at 21.2 µg/m³ near Cape Coral. Origin traced to June 2022 Saharan dust plume.
Reviewed source 3Agency/press 1
Origin: Sahara; western Africa
51.8 µg/m³ peak ≈ 2.5 cigarettes per person 9.2M people affected 1 top-ten day
Dust over 6 metros, 6 days, peaking at 51.8 µg/m³ near Baton Rouge. Origin traced to Sahara; western Africa.
EPA AQS 12NWS alert 1Agency/press 3internet-archive-wayback-cdx 4
Origin: Central America; Mexico; western Africa
40.6 µg/m³ peak ≈ 1.4 cigarettes per person 915k people affected
Mixed causes over McAllen, 1 day, peaking at 40.6 µg/m³ near McAllen. Origin traced to Central America; Mexico; western Africa.
EPA AQS 1Agency/press 1
21 µg/m³ peak ≈ 0.7 cigarettes per person 861k people affected
Dust over Cape Coral, 1 day, peaking at 21 µg/m³ near Cape Coral.
Reviewed source 1Agency/press 1
Origin: Four Corners; New Mexico
27.3 µg/m³ peak ≈ 1.0 cigarettes per person 778k people affected
Mixed causes over Colorado Springs, 1 day, peaking at 27.3 µg/m³ near Colorado Springs. Origin traced to Four Corners; New Mexico.
35.3 µg/m³ peak ≈ 1.2 cigarettes per person 661k people affected
Prescribed fire over Wichita, 1 day, peaking at 35.3 µg/m³ near Wichita.
Agency/press 1
Cited: Kansas Department of Health and Environment
40.8 µg/m³ peak ≈ 1.5 cigarettes per person 2.4M people affected
Dust over Las Vegas, 1 day, peaking at 40.8 µg/m³ near Las Vegas.
Origin: Central America; Mexico
49.9 µg/m³ peak ≈ 1.9 cigarettes per person 915k people affected
Wildfire smoke over McAllen, 1 day, peaking at 49.9 µg/m³ near McAllen. Origin traced to Central America; Mexico.
54 µg/m³ peak ≈ 2.0 cigarettes per person 1.1M people affected 1 top-ten day
Wildfire smoke over Tulsa, 1 day, peaking at 54 µg/m³ near Tulsa.
Reviewed source 1internet-archive-wayback-cdx 1
24 µg/m³ peak ≈ 0.8 cigarettes per person 740k people affected
Prescribed fire over Deltona, 1 day, peaking at 24 µg/m³ near Deltona.
Agency/press 1
Cited: Florida Forest Service
35.6 µg/m³ peak ≈ 1.2 cigarettes per person 606k people affected
Other over Jackson, 1 day, peaking at 35.6 µg/m³ near Jackson.
Agency/press 1internet-archive-wayback-cdx 5
50.3 µg/m³ peak ≈ 1.8 cigarettes per person 705k people affected 1 top-ten day
Other over Winston, 1 day, peaking at 50.3 µg/m³ near Winston.
36.9 µg/m³ peak ≈ 1.4 cigarettes per person 926k people affected
Dust over Albuquerque, 1 day, peaking at 36.9 µg/m³ near Albuquerque.
EPA AQS 1News 1
23.9 µg/m³ peak ≈ 0.8 cigarettes per person 853k people affected
Fireworks over Lakeland, 1 day, peaking at 23.9 µg/m³ near Lakeland.
Origin: Augusta-Richmond County, GA-SC
43.6 µg/m³ peak ≈ 1.5 cigarettes per person 637k people affected
Prescribed fire over Augusta, 1 day, peaking at 43.6 µg/m³ near Augusta. Origin traced to Augusta-Richmond County, GA-SC.
Origin: Chattanooga, TN-GA
39.3 µg/m³ peak ≈ 1.3 cigarettes per person 588k people affected
Prescribed fire over Chattanooga, 1 day, peaking at 39.3 µg/m³ near Chattanooga. Origin traced to Chattanooga, TN-GA.
Origin: Winston-Salem, NC
44.9 µg/m³ peak ≈ 1.6 cigarettes per person 705k people affected
Wildfire smoke over Winston, 1 day, peaking at 44.9 µg/m³ near Winston. Origin traced to Winston-Salem, NC.
EPA AQS 1News 1
27.5 µg/m³ peak ≈ 1.0 cigarettes per person 1.1M people affected
Dust over Tucson, 1 day, peaking at 27.5 µg/m³ near Tucson.
Reviewed source 2
Origin: Fresno, CA
147.7 µg/m³ peak ≈ 6.1 cigarettes per person 1.2M people affected 1 top-ten day
Wildfire smoke over Fresno, 1 day, peaking at 147.7 µg/m³ near Fresno. Origin traced to Fresno, CA.
EPA AQS 2News 1gdelt-doc-api 2
Origin: Boise City, ID
58.6 µg/m³ peak ≈ 2.3 cigarettes per person 846k people affected
Wildfire smoke over Boise City, 1 day, peaking at 58.6 µg/m³ near Boise City. Origin traced to Boise City, ID.
EPA AQS 2NWS alert 1
Origin: Cape Coral-Fort Myers, FL; Palm Bay-Melbourne-Titusville, FL
27 µg/m³ peak ≈ 0.9 cigarettes per person 1.5M people affected 2 top-ten days
Dust over 2 metros, 1 day, peaking at 27 µg/m³ near Palm Bay. Origin traced to Cape Coral-Fort Myers, FL; Palm Bay-Melbourne-Titusville, FL.
Agency/press 1internet-archive-wayback-cdx 1
Origin: Sacramento--Roseville--Arden-Arcade, CA
265.7 µg/m³ peak ≈ 21.3 cigarettes per person 2.5M people affected 1 city record set
Wildfire smoke over Sacramento, 3 days, peaking at 265.7 µg/m³ near Sacramento. 1 metro set an all-time record. Origin traced to Sacramento--Roseville--Arden-Arcade, CA.
EPA AQS 3Agency/press 1
Origin: Lakeland-Winter Haven, FL; Palm Bay-Melbourne-Titusville, FL
23.8 µg/m³ peak ≈ 1.1 cigarettes per person 1.5M people affected
Dust over 2 metros, 2 days, peaking at 23.8 µg/m³ near Palm Bay. Origin traced to Lakeland-Winter Haven, FL; Palm Bay-Melbourne-Titusville, FL.
Origin: Las Vegas-Henderson-Paradise, NV
59.3 µg/m³ peak ≈ 2.3 cigarettes per person 2.4M people affected 1 top-ten day
Wildfire smoke over Las Vegas, 1 day, peaking at 59.3 µg/m³ near Las Vegas. Origin traced to Las Vegas-Henderson-Paradise, NV.
EPA AQS 1Agency/press 1
Origin: Boise City, ID
82.6 µg/m³ peak ≈ 5.8 cigarettes per person 846k people affected 1 top-ten day
Wildfire smoke over Boise City, 2 days, peaking at 82.6 µg/m³ near Boise City. Origin traced to Boise City, ID.
EPA AQS 4NWS alert 1
Origin: Spokane-Spokane Valley, WA
123.7 µg/m³ peak ≈ 10.1 cigarettes per person 605k people affected
Wildfire smoke over Spokane, 2 days, peaking at 123.7 µg/m³ near Spokane. Origin traced to Spokane-Spokane Valley, WA.
EPA AQS 2Agency/press 1
Origin: Albuquerque, NM
84 µg/m³ peak ≈ 5.2 cigarettes per person 926k people affected 1 city record set
Wildfire smoke over Albuquerque, 2 days, peaking at 84 µg/m³ near Albuquerque. 1 metro set an all-time record. Origin traced to Albuquerque, NM.
NWS alert 1Agency/press 1
Origin: Sacramento--Roseville--Arden-Arcade, CA
127.2 µg/m³ peak ≈ 5.4 cigarettes per person 2.5M people affected 1 top-ten day
Wildfire smoke over Sacramento, 1 day, peaking at 127.2 µg/m³ near Sacramento. Origin traced to Sacramento--Roseville--Arden-Arcade, CA.
EPA AQS 1Agency/press 1
Origin: Las Vegas-Henderson-Paradise, NV
100.7 µg/m³ peak ≈ 4.2 cigarettes per person 2.4M people affected 1 city record set
Wildfire smoke over Las Vegas, 1 day, peaking at 100.7 µg/m³ near Las Vegas. 1 metro set an all-time record. Origin traced to Las Vegas-Henderson-Paradise, NV.
EPA AQS 1News 1gdelt-doc-api 2
Origin: Colorado Springs, CO; Denver-Aurora-Lakewood, CO
64.8 µg/m³ peak ≈ 4.4 cigarettes per person 3.8M people affected 2 top-ten days
Wildfire smoke over 2 metros, 2 days, peaking at 64.8 µg/m³ near Denver. Origin traced to Colorado Springs, CO; Denver-Aurora-Lakewood, CO.
NWS alert 2Agency/press 1
Origin: Spokane-Spokane Valley, WA
105 µg/m³ peak ≈ 4.4 cigarettes per person 605k people affected
Wildfire smoke over Spokane, 1 day, peaking at 105 µg/m³ near Spokane. Origin traced to Spokane-Spokane Valley, WA.
EPA AQS 1NWS alert 1Agency/press 1
Origin: Des Moines-West Des Moines, IA; Kansas City, MO-KS; Oklahoma City, OK; Omaha-Council Bluffs, NE-IA; Tulsa, OK; Wichita, KS
53.5 µg/m³ peak ≈ 3.1 cigarettes per person 7.2M people affected 4 top-ten days
Wildfire smoke over 6 metros, 3 days, peaking at 53.5 µg/m³ near Kansas City. Origin traced to Des Moines-West Des Moines, IA; Kansas City, MO-KS; Oklahoma City, OK; Omaha-Council Bluffs, NE-IA; Tulsa, OK; Wichita, KS.
EPA AQS 7NWS alert 1News 2gdelt-doc-api 8internet-archive-wayback-cdx 5
Origin: Colorado Springs, CO
29 µg/m³ peak ≈ 1.1 cigarettes per person 778k people affected
Wildfire smoke over Colorado Springs, 1 day, peaking at 29 µg/m³ near Colorado Springs. Origin traced to Colorado Springs, CO.
NWS alert 1News 1gdelt-doc-api 6
Origin: Spokane-Spokane Valley, WA
85.9 µg/m³ peak ≈ 3.6 cigarettes per person 605k people affected
Wildfire smoke over Spokane, 1 day, peaking at 85.9 µg/m³ near Spokane. Origin traced to Spokane-Spokane Valley, WA.
EPA AQS 1NWS alert 1Agency/press 1
Origin: Omaha-Council Bluffs, NE-IA
45.3 µg/m³ peak ≈ 1.7 cigarettes per person 1.0M people affected
Wildfire smoke over Omaha, 1 day, peaking at 45.3 µg/m³ near Omaha. Origin traced to Omaha-Council Bluffs, NE-IA.
EPA AQS 1News 1gdelt-doc-api 10
Origin: Minneapolis-St. Paul-Bloomington, MN-WI
115.6 µg/m³ peak ≈ 10.2 cigarettes per person 3.8M people affected 1 top-ten day
Wildfire smoke over Minneapolis, 3 days, peaking at 115.6 µg/m³ near Minneapolis. Origin traced to Minneapolis-St. Paul-Bloomington, MN-WI.
EPA AQS 3NWS alert 1Agency/press 1
Origin: Boston-Cambridge-Newton, MA-NH; Hartford-West Hartford-East Hartford, CT; New Haven-Milford, CT; Providence-Warwick, RI-MA; Worcester, MA-CT
59 µg/m³ peak ≈ 2.0 cigarettes per person 9.4M people affected 3 top-ten days
Wildfire smoke over 5 metros, 1 day, peaking at 59 µg/m³ near Boston. Origin traced to Boston-Cambridge-Newton, MA-NH; Hartford-West Hartford-East Hartford, CT; New Haven-Milford, CT; Providence-Warwick, RI-MA; Worcester, MA-CT.
EPA AQS 2Agency/press 1
Origin: Nashville-Davidson--Murfreesboro--Franklin, TN
41.5 µg/m³ peak ≈ 1.4 cigarettes per person 2.2M people affected
Wildfire smoke over Nashville, 1 day, peaking at 41.5 µg/m³ near Nashville. Origin traced to Nashville-Davidson--Murfreesboro--Franklin, TN.
EPA AQS 1News 1internet-archive-wayback-cdx 2gdelt-doc-api 3
35.8 µg/m³ peak ≈ 2.3 cigarettes per person 1.5M people affected
Wildfire smoke over Oklahoma City, 2 days, peaking at 35.8 µg/m³ near Oklahoma City.
Origin: Albany-Schenectady-Troy, NY; Allentown-Bethlehem-Easton, PA-NJ; Bridgeport-Stamford-Norwalk, CT; Hartford-West Hartford-East Hartford, CT; New Haven-Milford, CT; New York-Newark-Jersey City, NY-NJ-PA; Philadelphia-Camden-Wilmington, PA-NJ-DE-MD; Richmond, VA; Scranton--Wilkes-Barre--Hazleton, PA; Syracuse, NY; Worcester, MA-CT
62.1 µg/m³ peak ≈ 2.1 cigarettes per person 34M people affected
Wildfire smoke over 11 metros, 2 days, peaking at 62.1 µg/m³ near New York. Origin traced to Albany-Schenectady-Troy, NY; Allentown-Bethlehem-Easton, PA-NJ; Bridgeport-Stamford-Norwalk, CT; Hartford-West Hartford-East Hartford, CT; New Haven-Milford, CT; New York-Newark-Jersey City, NY-NJ-PA; Philadelphia-Camden-Wilmington, PA-NJ-DE-MD; Richmond, VA; Scranton--Wilkes-Barre--Hazleton, PA; Syracuse, NY; Worcester, MA-CT.
EPA AQS 7Agency/press 2
Origin: Nashville-Davidson--Murfreesboro--Franklin, TN
41.1 µg/m³ peak ≈ 1.4 cigarettes per person 2.2M people affected
Mixed causes over Nashville, 1 day, peaking at 41.1 µg/m³ near Nashville. Origin traced to Nashville-Davidson--Murfreesboro--Franklin, TN.
EPA AQS 2internet-archive-wayback-cdx 9
74 µg/m³ peak ≈ 2.8 cigarettes per person 2.8M people affected 1 top-ten day
Fireworks over St. Louis, 1 day, peaking at 74 µg/m³ near St. Louis.
Origin: Washington-Arlington-Alexandria, DC-VA-MD-WV
58.9 µg/m³ peak ≈ 2.2 cigarettes per person 6.4M people affected
Fireworks over Washington, 1 day, peaking at 58.9 µg/m³ near Washington. Origin traced to Washington-Arlington-Alexandria, DC-VA-MD-WV.
EPA AQS 2gdelt-doc-api 3
54 µg/m³ peak ≈ 2.0 cigarettes per person 2.3M people affected 1 top-ten day
Fireworks over Kansas City, 1 day, peaking at 54 µg/m³ near Kansas City.
internet-archive-wayback-cdx 3
Origin: Augusta-Richmond County, GA-SC; Charlotte-Concord-Gastonia, NC-SC; Lakeland-Winter Haven, FL; North Port-Sarasota-Bradenton, FL
46.6 µg/m³ peak ≈ 1.3 cigarettes per person 5.3M people affected 1 top-ten day
Fireworks over 4 metros, 2 days, peaking at 46.6 µg/m³ near Charlotte. Origin traced to Augusta-Richmond County, GA-SC; Charlotte-Concord-Gastonia, NC-SC; Lakeland-Winter Haven, FL; North Port-Sarasota-Bradenton, FL.
EPA AQS 7Agency/press 1
42.8 µg/m³ peak ≈ 1.5 cigarettes per person 1.1M people affected 1 top-ten day
Fireworks over Tulsa, 1 day, peaking at 42.8 µg/m³ near Tulsa.
internet-archive-wayback-cdx 5
42.8 µg/m³ peak ≈ 1.5 cigarettes per person 6.5M people affected
Dust over Miami, 1 day, peaking at 42.8 µg/m³ near Miami.
Reviewed source 1News 1
Origin: Albuquerque, NM
37.3 µg/m³ peak ≈ 1.4 cigarettes per person 926k people affected
Wildfire smoke over Albuquerque, 1 day, peaking at 37.3 µg/m³ near Albuquerque. Origin traced to Albuquerque, NM.
NWS alert 1Agency/press 2
Named source Mescal Fire, Telegraph Fire · Albuquerque, NM
57.9 µg/m³ peak ≈ 3.8 cigarettes per person 926k people affected 1 top-ten day
Wildfire smoke over Albuquerque, 2 days, peaking at 57.9 µg/m³ near Albuquerque. Origin traced to Albuquerque, NM.
NWS alert 1Agency/press 2
Origin: Knoxville, TN
55.2 µg/m³ peak ≈ 2.0 cigarettes per person 958k people affected
Prescribed fire over Knoxville, 1 day, peaking at 55.2 µg/m³ near Knoxville. Origin traced to Knoxville, TN.
EPA AQS 1Agency/press 1
Origin: Denver-Aurora-Lakewood, CO
55.7 µg/m³ peak ≈ 3.9 cigarettes per person 3.1M people affected
Other over Denver, 2 days, peaking at 55.7 µg/m³ near Denver. Origin traced to Denver-Aurora-Lakewood, CO.
News 1gdelt-doc-api 1
Origin: Augusta-Richmond County, GA-SC
41.2 µg/m³ peak ≈ 1.4 cigarettes per person 637k people affected
Prescribed fire over Augusta, 1 day, peaking at 41.2 µg/m³ near Augusta. Origin traced to Augusta-Richmond County, GA-SC.
EPA AQS 1Agency/press 1
Origin: Kansas City, MO-KS
41.1 µg/m³ peak ≈ 1.4 cigarettes per person 2.3M people affected
Wildfire smoke over Kansas City, 1 day, peaking at 41.1 µg/m³ near Kansas City. Origin traced to Kansas City, MO-KS.
Origin: Tulsa, OK
79.6 µg/m³ peak ≈ 4.4 cigarettes per person 1.1M people affected 1 city record set
Wildfire smoke over Tulsa, 2 days, peaking at 79.6 µg/m³ near Tulsa. 1 metro set an all-time record. Origin traced to Tulsa, OK.
News 1internet-archive-wayback-cdx 2gdelt-doc-api 1
Origin: Augusta-Richmond County, GA-SC
53.4 µg/m³ peak ≈ 1.9 cigarettes per person 637k people affected 1 top-ten day
Prescribed fire over Augusta, 1 day, peaking at 53.4 µg/m³ near Augusta. Origin traced to Augusta-Richmond County, GA-SC.
EPA AQS 1Agency/press 2
Origin: Houston-The Woodlands-Sugar Land, TX
47.4 µg/m³ peak ≈ 1.6 cigarettes per person 7.8M people affected 1 top-ten day
Dust over Houston, 1 day, peaking at 47.4 µg/m³ near Houston. Origin traced to Houston-The Woodlands-Sugar Land, TX.
Agency/press 2gdelt-doc-api 2
Origin: Phoenix-Mesa-Scottsdale, AZ; Tucson, AZ
131.9 µg/m³ peak ≈ 6.6 cigarettes per person 6.3M people affected 1 top-ten day
Mixed causes over 2 metros, 2 days, peaking at 131.9 µg/m³ near Phoenix. Origin traced to Phoenix-Mesa-Scottsdale, AZ; Tucson, AZ.
EPA AQS 1Agency/press 2
63 µg/m³ peak ≈ 2.3 cigarettes per person 5.2M people affected
Mixed causes over Phoenix, 1 day, peaking at 63 µg/m³ near Phoenix.
Agency/press 1Reviewed source 1
52.4 µg/m³ peak ≈ 3.7 cigarettes per person 913k people affected 1 top-ten day
Residential combustion over Albany, 2 days, peaking at 52.4 µg/m³ near Albany.
52.8 µg/m³ peak ≈ 1.8 cigarettes per person 2.2M people affected
Stagnant pollution mixture over Indianapolis, 1 day, peaking at 52.8 µg/m³ near Indianapolis.
Reviewed source 3
Origin: Fresno, CA
131.6 µg/m³ peak ≈ 10.1 cigarettes per person 1.2M people affected
Wildfire smoke over Fresno, 2 days, peaking at 131.6 µg/m³ near Fresno. Origin traced to Fresno, CA.
EPA AQS 4Agency/press 1
Origin: San Diego-Carlsbad, CA
93 µg/m³ peak ≈ 14.6 cigarettes per person 3.3M people affected 1 top-ten day
Wildfire smoke over San Diego, 5 days, peaking at 93 µg/m³ near San Diego. Origin traced to San Diego-Carlsbad, CA.
EPA AQS 4Agency/press 1
Named source Glass Fire · San Francisco-Oakland-Hayward, CA; San Jose-Sunnyvale-Santa Clara, CA; Stockton-Lodi, CA
103.9 µg/m³ peak ≈ 6.2 cigarettes per person 7.5M people affected
Wildfire smoke over 3 metros, 3 days, peaking at 103.9 µg/m³ near San Francisco. Origin traced to San Francisco-Oakland-Hayward, CA; San Jose-Sunnyvale-Santa Clara, CA; Stockton-Lodi, CA.
EPA AQS 7Agency/press 2
Origin: Colorado Springs, CO; Denver-Aurora-Lakewood, CO
46.9 µg/m³ peak ≈ 1.8 cigarettes per person 3.8M people affected
Wildfire smoke over 2 metros, 2 days, peaking at 46.9 µg/m³ near Denver. Origin traced to Colorado Springs, CO; Denver-Aurora-Lakewood, CO.
EPA AQS 1NWS alert 2Agency/press 2
Origin: Boise City, ID
61.6 µg/m³ peak ≈ 12.1 cigarettes per person 846k people affected 1 top-ten day
Wildfire smoke over Boise City, 5 days, peaking at 61.6 µg/m³ near Boise City. Origin traced to Boise City, ID.
EPA AQS 10NWS record 4Agency/press 2
Origin: Portland-Vancouver-Hillsboro, OR-WA; Seattle-Tacoma-Bellevue, WA; Spokane-Spokane Valley, WA
513.4 µg/m³ peak ≈ 68.9 cigarettes per person 7.3M people affected 2 city records set, 3 top-ten days
Wildfire smoke over 3 metros, 9 days, peaking at 513.4 µg/m³ near Portland. 2 metros set an all-time record. Origin traced to Portland-Vancouver-Hillsboro, OR-WA; Seattle-Tacoma-Bellevue, WA; Spokane-Spokane Valley, WA.
EPA AQS 23NWS alert 2NWS record 7Agency/press 3
Origin: Fresno, CA; Los Angeles-Long Beach-Anaheim, CA; Oxnard-Thousand Oaks-Ventura, CA; Sacramento--Roseville--Arden-Arcade, CA; San Diego-Carlsbad, CA; San Francisco-Oakland-Hayward, CA; San Jose-Sunnyvale-Santa Clara, CA; Stockton-Lodi, CA
199.3 µg/m³ peak ≈ 13.8 cigarettes per person 28M people affected 1 city record set, 8 top-ten days
Wildfire smoke over 8 metros, 8 days, peaking at 199.3 µg/m³ near Fresno. 1 metro set an all-time record. Origin traced to Fresno, CA; Los Angeles-Long Beach-Anaheim, CA; Oxnard-Thousand Oaks-Ventura, CA; Sacramento--Roseville--Arden-Arcade, CA; San Diego-Carlsbad, CA; San Francisco-Oakland-Hayward, CA; San Jose-Sunnyvale-Santa Clara, CA; Stockton-Lodi, CA.
EPA AQS 67NWS alert 1Agency/press 4
Origin: Bakersfield, CA
125.4 µg/m³ peak ≈ 5.1 cigarettes per person 923k people affected 1 top-ten day
Wildfire smoke over Bakersfield, 1 day, peaking at 125.4 µg/m³ near Bakersfield. Origin traced to Bakersfield, CA.
EPA AQS 2Agency/press 2
Origin: Las Vegas-Henderson-Paradise, NV
49.8 µg/m³ peak ≈ 1.9 cigarettes per person 2.4M people affected 1 top-ten day
Mixed causes over Las Vegas, 1 day, peaking at 49.8 µg/m³ near Las Vegas. Origin traced to Las Vegas-Henderson-Paradise, NV.
EPA AQS 1Agency/press 2
Named source Cameron Peak Fire · Colorado Springs, CO; Denver-Aurora-Lakewood, CO
49.7 µg/m³ peak ≈ 1.7 cigarettes per person 3.8M people affected
Wildfire smoke over 2 metros, 2 days, peaking at 49.7 µg/m³ near Denver. Origin traced to Colorado Springs, CO; Denver-Aurora-Lakewood, CO.
Agency/press 2
Named source Cameron Peak Fire · Colorado Springs, CO; Denver-Aurora-Lakewood, CO
51.6 µg/m³ peak ≈ 3.5 cigarettes per person 3.8M people affected
Wildfire smoke over 2 metros, 2 days, peaking at 51.6 µg/m³ near Denver. Origin traced to Colorado Springs, CO; Denver-Aurora-Lakewood, CO.
NWS alert 1Agency/press 2
Origin: Ogden-Clearfield, UT; Salt Lake City, UT
71.5 µg/m³ peak ≈ 2.8 cigarettes per person 2.0M people affected
Wildfire smoke over 2 metros, 1 day, peaking at 71.5 µg/m³ near Salt Lake City. Origin traced to Ogden-Clearfield, UT; Salt Lake City, UT.
EPA AQS 3Agency/press 2
Origin: Bakersfield, CA; Fresno, CA; Sacramento--Roseville--Arden-Arcade, CA; San Francisco-Oakland-Hayward, CA; San Jose-Sunnyvale-Santa Clara, CA; Stockton-Lodi, CA
158.6 µg/m³ peak ≈ 11.4 cigarettes per person 12M people affected 1 city record set, 3 top-ten days
Wildfire smoke over 6 metros, 6 days, peaking at 158.6 µg/m³ near Bakersfield. 1 metro set an all-time record. Origin traced to Bakersfield, CA; Fresno, CA; Sacramento--Roseville--Arden-Arcade, CA; San Francisco-Oakland-Hayward, CA; San Jose-Sunnyvale-Santa Clara, CA; Stockton-Lodi, CA.
EPA AQS 38NWS record 1Agency/press 3
Origin: Buffalo-Cheektowaga-Niagara Falls, NY; Cleveland-Elyria, OH
61.8 µg/m³ peak ≈ 2.2 cigarettes per person 3.3M people affected 2 top-ten days
Fireworks over 2 metros, 1 day, peaking at 61.8 µg/m³ near Cleveland. Origin traced to Buffalo-Cheektowaga-Niagara Falls, NY; Cleveland-Elyria, OH.
Origin: Memphis, TN-MS-AR
57.9 µg/m³ peak ≈ 2.2 cigarettes per person 1.3M people affected 1 city record set
Fireworks over Memphis, 1 day, peaking at 57.9 µg/m³ near Memphis. 1 metro set an all-time record. Origin traced to Memphis, TN-MS-AR.
47.9 µg/m³ peak ≈ 1.7 cigarettes per person 1.8M people affected
Fireworks over 2 metros, 1 day, peaking at 47.9 µg/m³ near Grand Rapids.
Reviewed source 1
Origin: Los Angeles-Long Beach-Anaheim, CA
175 µg/m³ peak ≈ 10.7 cigarettes per person 13M people affected 1 city record set
Fireworks over Los Angeles, 2 days, peaking at 175 µg/m³ near Los Angeles. 1 metro set an all-time record. Origin traced to Los Angeles-Long Beach-Anaheim, CA.
EPA AQS 2Agency/press 2
Origin: Chattanooga, TN-GA; Des Moines-West Des Moines, IA; Greenville-Anderson-Mauldin, SC; Kansas City, MO-KS; Omaha-Council Bluffs, NE-IA; Wichita, KS
123.5 µg/m³ peak ≈ 3.7 cigarettes per person 6.3M people affected 1 city record set, 4 top-ten days
Fireworks over 6 metros, 2 days, peaking at 123.5 µg/m³ near Des Moines. 1 metro set an all-time record. Origin traced to Chattanooga, TN-GA; Des Moines-West Des Moines, IA; Greenville-Anderson-Mauldin, SC; Kansas City, MO-KS; Omaha-Council Bluffs, NE-IA; Wichita, KS.
EPA AQS 10Agency/press 2News 1
Origin: Minneapolis-St. Paul-Bloomington, MN-WI
72.6 µg/m³ peak ≈ 2.9 cigarettes per person 3.8M people affected 1 top-ten day
Fireworks over Minneapolis, 1 day, peaking at 72.6 µg/m³ near Minneapolis. Origin traced to Minneapolis-St. Paul-Bloomington, MN-WI.
EPA AQS 1Agency/press 1
Origin: St. Louis, MO-IL
62.5 µg/m³ peak ≈ 4.0 cigarettes per person 2.8M people affected 1 top-ten day
Fireworks over St. Louis, 2 days, peaking at 62.5 µg/m³ near St. Louis. Origin traced to St. Louis, MO-IL.
Origin: Washington-Arlington-Alexandria, DC-VA-MD-WV
62.2 µg/m³ peak ≈ 2.3 cigarettes per person 6.4M people affected 1 top-ten day
Fireworks over Washington, 1 day, peaking at 62.2 µg/m³ near Washington. Origin traced to Washington-Arlington-Alexandria, DC-VA-MD-WV.
EPA AQS 1Agency/press 2
Origin: Miami-Fort Lauderdale-West Palm Beach, FL
45.2 µg/m³ peak ≈ 1.7 cigarettes per person 6.5M people affected
Fireworks over Miami, 1 day, peaking at 45.2 µg/m³ near Miami. Origin traced to Miami-Fort Lauderdale-West Palm Beach, FL.
39 µg/m³ peak ≈ 1.3 cigarettes per person 8.3M people affected
Fireworks over Dallas, 1 day, peaking at 39 µg/m³ near Dallas.
Reviewed source 2
Origin: Austin-Round Rock, TX; Charleston-North Charleston, SC; Columbia, SC; Dallas-Fort Worth-Arlington, TX; Houston-The Woodlands-Sugar Land, TX; Jackson, MS; Little Rock-North Little Rock-Conway, AR; McAllen-Edinburg-Mission, TX; Nashville-Davidson--Murfreesboro--Franklin, TN; Oklahoma City, OK; Sahara Desert; San Antonio-New Braunfels, TX; Tulsa, OK; Wichita, KS
64.9 µg/m³ peak ≈ 2.0 cigarettes per person 31M people affected 2 city records set, 9 top-ten days
Dust over 13 metros, 3 days, peaking at 64.9 µg/m³ near San Antonio. 2 metros set an all-time record. Origin traced to Austin-Round Rock, TX; Charleston-North Charleston, SC; Columbia, SC; Dallas-Fort Worth-Arlington, TX; Houston-The Woodlands-Sugar Land, TX; Jackson, MS; Little Rock-North Little Rock-Conway, AR; McAllen-Edinburg-Mission, TX; Nashville-Davidson--Murfreesboro--Franklin, TN; Oklahoma City, OK; Sahara Desert; San Antonio-New Braunfels, TX; Tulsa, OK; Wichita, KS.
EPA AQS 10NWS alert 2Agency/press 5News 2internet-archive-wayback-cdx 5
Cited: Saharan dust plume
Origin: Albuquerque, NM
35.1 µg/m³ peak ≈ 1.3 cigarettes per person 926k people affected
Wildfire smoke over Albuquerque, 1 day, peaking at 35.1 µg/m³ near Albuquerque. Origin traced to Albuquerque, NM.
NWS alert 1News 1gdelt-doc-api 2
21.3 µg/m³ peak ≈ 0.7 cigarettes per person 861k people affected
Prescribed fire over Cape Coral, 1 day, peaking at 21.3 µg/m³ near Cape Coral.
Reviewed source 1internet-archive-wayback-cdx 3
Origin: Wichita, KS
40.5 µg/m³ peak ≈ 1.5 cigarettes per person 661k people affected
Prescribed fire over Wichita, 1 day, peaking at 40.5 µg/m³ near Wichita. Origin traced to Wichita, KS.
Origin: Phoenix-Mesa-Scottsdale, AZ
149.1 µg/m³ peak ≈ 6.2 cigarettes per person 5.2M people affected 1 top-ten day
Mixed causes over Phoenix, 1 day, peaking at 149.1 µg/m³ near Phoenix. Origin traced to Phoenix-Mesa-Scottsdale, AZ.
Origin: Tampa-St. Petersburg-Clearwater, FL
38.4 µg/m³ peak ≈ 1.3 cigarettes per person 3.4M people affected
Fireworks over Tampa, 1 day, peaking at 38.4 µg/m³ near Tampa. Origin traced to Tampa-St. Petersburg-Clearwater, FL.
110.6 µg/m³ peak ≈ 6.0 cigarettes per person 7.8M people affected 1 city record set
Fireworks over Houston, 2 days, peaking at 110.6 µg/m³ near Houston. 1 metro set an all-time record.
Origin: Denver metropolitan area, Colorado
58.6 µg/m³ peak ≈ 2.0 cigarettes per person 3.8M people affected 1 top-ten day
Winter inversion over 2 metros, 2 days, peaking at 58.6 µg/m³ near Denver. Origin traced to Denver metropolitan area, Colorado.
Agency/press 2
55.4 µg/m³ peak ≈ 4.0 cigarettes per person 615k people affected
Temperature inversion over Harrisburg, 2 days, peaking at 55.4 µg/m³ near Harrisburg.
Origin: Austin-Round Rock-Georgetown metropolitan area, Texas
90.8 µg/m³ peak ≈ 3.0 cigarettes per person 10M people affected 2 top-ten days
Fireworks over 2 metros, 1 day, peaking at 90.8 µg/m³ near Houston. Origin traced to Austin-Round Rock-Georgetown metropolitan area, Texas.
Agency/press 1
47.7 µg/m³ peak ≈ 1.8 cigarettes per person 2.8M people affected 1 top-ten day
Fireworks over San Antonio, 1 day, peaking at 47.7 µg/m³ near San Antonio.
Reviewed source 1Agency/press 1
Named source Camp Fire
228.4 µg/m³ peak ≈ 46.3 cigarettes per person 9.9M people affected 3 city records set, 4 top-ten days
Wildfire smoke over 4 metros, 12 days, peaking at 228.4 µg/m³ near Sacramento. 3 metros set an all-time record.
EPA AQS 50NWS record 25Agency/press 3
Named source Dollar Ridge Fire, Bald Mountain Fire, Pole Creek Fire
76.2 µg/m³ peak ≈ 3.1 cigarettes per person 761k people affected
Wildfire smoke over Provo, 1 day, peaking at 76.2 µg/m³ near Provo.
EPA AQS 1Agency/press 1
Named source Pole Creek Fire, Bald Mountain Fire, Dollar Ridge Fire
74.5 µg/m³ peak ≈ 3.1 cigarettes per person 761k people affected
Wildfire smoke over Provo, 1 day, peaking at 74.5 µg/m³ near Provo.
EPA AQS 1Agency/press 1
105.3 µg/m³ peak ≈ 12.8 cigarettes per person 4.1M people affected 1 top-ten day
Wildfire smoke over Seattle, 3 days, peaking at 105.3 µg/m³ near Seattle.
EPA AQS 3NWS alert 1NWS record 11Agency/press 2
55.4 µg/m³ peak ≈ 2.4 cigarettes per person 3.8M people affected 1 top-ten day
Wildfire smoke over 2 metros, 3 days, peaking at 55.4 µg/m³ near Denver.
News 1gdelt-doc-api 7
185 µg/m³ peak ≈ 14.6 cigarettes per person 605k people affected 1 top-ten day
Wildfire smoke over Spokane, 2 days, peaking at 185 µg/m³ near Spokane.
EPA AQS 2NWS alert 1NWS record 11Agency/press 1
40.1 µg/m³ peak ≈ 1.4 cigarettes per person 606k people affected 1 top-ten day
Dust over Jackson, 1 day, peaking at 40.1 µg/m³ near Jackson.
Reviewed source 3internet-archive-wayback-cdx 21gdelt-doc-api 4
95.9 µg/m³ peak ≈ 4.0 cigarettes per person 4.1M people affected
Wildfire smoke over Seattle, 1 day, peaking at 95.9 µg/m³ near Seattle.
EPA AQS 1NWS record 7Agency/press 2
39.2 µg/m³ peak ≈ 1.2 cigarettes per person 7.8M people affected
Dust over Houston, 1 day, peaking at 39.2 µg/m³ near Houston.
Reviewed source 1
49.6 µg/m³ peak ≈ 1.9 cigarettes per person 2.4M people affected
Mixed causes over Las Vegas, 1 day, peaking at 49.6 µg/m³ near Las Vegas.
EPA AQS 2News 1gdelt-doc-api 3
56.9 µg/m³ peak ≈ 3.5 cigarettes per person 11M people affected 1 top-ten day
Dust over 2 metros, 2 days, peaking at 56.9 µg/m³ near Dallas.
63.5 µg/m³ peak ≈ 2.3 cigarettes per person 5.2M people affected
Dust over Phoenix, 1 day, peaking at 63.5 µg/m³ near Phoenix.
65.8 µg/m³ peak ≈ 2.4 cigarettes per person 2.2M people affected 1 top-ten day
Fireworks over Indianapolis, 1 day, peaking at 65.8 µg/m³ near Indianapolis.
49.7 µg/m³ peak ≈ 3.1 cigarettes per person 11M people affected 1 top-ten day
Dust over 2 metros, 2 days, peaking at 49.7 µg/m³ near Dallas.
EPA AQS 2Agency/press 1
41.3 µg/m³ peak ≈ 1.5 cigarettes per person 915k people affected
Dust over McAllen, 1 day, peaking at 41.3 µg/m³ near McAllen.
Agency/press 1Reviewed source 2
37.4 µg/m³ peak ≈ 1.4 cigarettes per person 861k people affected 1 top-ten day
Other over Cape Coral, 1 day, peaking at 37.4 µg/m³ near Cape Coral.
Agency/press 1internet-archive-wayback-cdx 1
43.8 µg/m³ peak ≈ 1.6 cigarettes per person 1.5M people affected 1 top-ten day
Wildfire smoke over Oklahoma City, 1 day, peaking at 43.8 µg/m³ near Oklahoma City.
EPA AQS 1Agency/press 1
41.3 µg/m³ peak ≈ 1.4 cigarettes per person 637k people affected
Prescribed fire over Augusta, 1 day, peaking at 41.3 µg/m³ near Augusta.
Reviewed source 5
48.5 µg/m³ peak ≈ 1.7 cigarettes per person 637k people affected 1 top-ten day
Prescribed fire over Augusta, 1 day, peaking at 48.5 µg/m³ near Augusta.
Reviewed source 1
46.6 µg/m³ peak ≈ 1.7 cigarettes per person 3.1M people affected
Temperature inversion over Denver, 1 day, peaking at 46.6 µg/m³ near Denver.
Reviewed source 3
134.1 µg/m³ peak ≈ 7.4 cigarettes per person 6.3M people affected 2 top-ten days
Fireworks over 2 metros, 2 days, peaking at 134.1 µg/m³ near Phoenix.
111 µg/m³ peak ≈ 4.1 cigarettes per person 19M people affected 1 top-ten day
Fireworks over 3 metros, 3 days, peaking at 111 µg/m³ near Los Angeles.
EPA AQS 5Agency/press 1
89.9 µg/m³ peak ≈ 3.4 cigarettes per person 13M people affected
Mixed causes over Los Angeles, 1 day, peaking at 89.9 µg/m³ near Los Angeles.
86.6 µg/m³ peak ≈ 3.4 cigarettes per person 5.2M people affected
Residential combustion over Phoenix, 1 day, peaking at 86.6 µg/m³ near Phoenix.
Named source Thomas Fire
100.7 µg/m³ peak ≈ 7.2 cigarettes per person 835k people affected 1 top-ten day
Wildfire smoke over Oxnard, 4 days, peaking at 100.7 µg/m³ near Oxnard.
EPA AQS 3Agency/press 4
Cited: CAL FIRE
89.4 µg/m³ peak ≈ 3.6 cigarettes per person 4.6M people affected
Wildfire smoke over San Francisco, 1 day, peaking at 89.4 µg/m³ near San Francisco.
82.6 µg/m³ peak ≈ 3.4 cigarettes per person 846k people affected 1 top-ten day
Wildfire smoke over Boise City, 1 day, peaking at 82.6 µg/m³ near Boise City.
EPA AQS 2NWS record 6Agency/press 2
70.3 µg/m³ peak ≈ 3.8 cigarettes per person 6.7M people affected
Wildfire smoke over 2 metros, 2 days, peaking at 70.3 µg/m³ near Seattle.
EPA AQS 4NWS alert 1NWS record 5Agency/press 2
194.9 µg/m³ peak ≈ 35.5 cigarettes per person 605k people affected 1 top-ten day
Wildfire smoke over Spokane, 5 days, peaking at 194.9 µg/m³ near Spokane.
EPA AQS 5NWS alert 1NWS record 5Agency/press 1
62.3 µg/m³ peak ≈ 2.3 cigarettes per person 3.8M people affected 2 top-ten days
Wildfire smoke over 2 metros, 1 day, peaking at 62.3 µg/m³ near Denver.
EPA AQS 1Agency/press 1
68.5 µg/m³ peak ≈ 2.5 cigarettes per person 6.7M people affected
Wildfire smoke over 2 metros, 1 day, peaking at 68.5 µg/m³ near Seattle.
EPA AQS 1NWS record 2Agency/press 1
49.5 µg/m³ peak ≈ 1.9 cigarettes per person 754k people affected 1 top-ten day
Fireworks over Des Moines, 1 day, peaking at 49.5 µg/m³ near Des Moines.
News 1gdelt-doc-api 2
46.6 µg/m³ peak ≈ 1.7 cigarettes per person 2.4M people affected
Fireworks over Las Vegas, 1 day, peaking at 46.6 µg/m³ near Las Vegas.
32 µg/m³ peak ≈ 1.1 cigarettes per person 2.9M people affected
Wildfire smoke over Orlando, 1 day, peaking at 32 µg/m³ near Orlando.
35.9 µg/m³ peak ≈ 1.2 cigarettes per person 1.1M people affected
Wildfire smoke over Tulsa, 1 day, peaking at 35.9 µg/m³ near Tulsa.
Reviewed source 1internet-archive-wayback-cdx 2
75.3 µg/m³ peak ≈ 2.8 cigarettes per person 1.4M people affected
Temperature inversion over 2 metros, 2 days, peaking at 75.3 µg/m³ near Provo.
Reviewed source 1state-local-official-archive-discovery-v1 1
47.1 µg/m³ peak ≈ 1.7 cigarettes per person 5.3M people affected 2 top-ten days
Fireworks over 2 metros, 1 day, peaking at 47.1 µg/m³ near Austin.
127.3 µg/m³ peak ≈ 3.8 cigarettes per person 14M people affected 5 city records set, 8 top-ten days
Wildfire smoke over 9 metros, 12 days, peaking at 127.3 µg/m³ near Greenville. 5 metros set an all-time record.
EPA AQS 23NWS alert 1Agency/press 6
53.4 µg/m³ peak ≈ 1.9 cigarettes per person 883k people affected 1 top-ten day
Other over Baton Rouge, 1 day, peaking at 53.4 µg/m³ near Baton Rouge.
Reviewed source 2
69.9 µg/m³ peak ≈ 2.8 cigarettes per person 2.4M people affected 1 top-ten day
Dust over Las Vegas, 1 day, peaking at 69.9 µg/m³ near Las Vegas.
EPA AQS 1Agency/press 1
56.2 µg/m³ peak ≈ 2.1 cigarettes per person 3.8M people affected
Wildfire smoke over Minneapolis, 1 day, peaking at 56.2 µg/m³ near Minneapolis.
43 µg/m³ peak ≈ 1.5 cigarettes per person 1.8M people affected
Wildfire smoke over 2 metros, 1 day, peaking at 43 µg/m³ near Des Moines.
45.8 µg/m³ peak ≈ 1.7 cigarettes per person 1.0M people affected
Prescribed fire over Omaha, 1 day, peaking at 45.8 µg/m³ near Omaha.
EPA AQS 1Agency/press 2
Origin: Eastern Oklahoma wildfires
35.9 µg/m³ peak ≈ 1.2 cigarettes per person 1.1M people affected
Wildfire smoke over Tulsa, 1 day, peaking at 35.9 µg/m³ near Tulsa. Origin traced to Eastern Oklahoma wildfires.
Reviewed source 3internet-archive-wayback-cdx 1
152.1 µg/m³ peak ≈ 5.4 cigarettes per person 6.3M people affected 1 top-ten day
Mixed causes over 2 metros, 1 day, peaking at 152.1 µg/m³ near Phoenix.
Agency/press 1Reviewed source 2state-local-official-archive-discovery-v1 1
25.2 µg/m³ peak ≈ 0.8 cigarettes per person 853k people affected
Fireworks over Lakeland, 1 day, peaking at 25.2 µg/m³ near Lakeland.
Reviewed source 1 1
109.8 µg/m³ peak ≈ 4.6 cigarettes per person 2.5M people affected
Wildfire smoke over Sacramento, 1 day, peaking at 109.8 µg/m³ near Sacramento.
66.7 µg/m³ peak ≈ 5.0 cigarettes per person 2.5M people affected
Wildfire smoke over Portland, 2 days, peaking at 66.7 µg/m³ near Portland.
EPA AQS 2Agency/press 1
53 µg/m³ peak ≈ 1.8 cigarettes per person 3.8M people affected
Wildfire smoke over 2 metros, 2 days, peaking at 53 µg/m³ near Denver.
Agency/press 1Reviewed source 2
41.9 µg/m³ peak ≈ 1.4 cigarettes per person 2.3M people affected
Wildfire smoke over Kansas City, 1 day, peaking at 41.9 µg/m³ near Kansas City.
49.4 µg/m³ peak ≈ 1.8 cigarettes per person 702k people affected
Mixed causes over Akron, 1 day, peaking at 49.4 µg/m³ near Akron.
EPA AQS 2Agency/press 1
117.8 µg/m³ peak ≈ 3.7 cigarettes per person 21M people affected 4 top-ten days
Fireworks over 6 metros, 2 days, peaking at 117.8 µg/m³ near Chicago.
EPA AQS 13Agency/press 3
48.7 µg/m³ peak ≈ 1.8 cigarettes per person 3.1M people affected
Temperature inversion over Denver, 1 day, peaking at 48.7 µg/m³ near Denver.
Reviewed source 3
107.8 µg/m³ peak ≈ 4.3 cigarettes per person 923k people affected
Stagnant pollution mixture over Bakersfield, 1 day, peaking at 107.8 µg/m³ near Bakersfield.
Reviewed source 2
55.3 µg/m³ peak ≈ 2.2 cigarettes per person 846k people affected
Temperature inversion over Boise City, 1 day, peaking at 55.3 µg/m³ near Boise City.
Reviewed source 1 1
40.9 µg/m³ peak ≈ 1.5 cigarettes per person 870k people affected
Fireworks over Charleston, 1 day, peaking at 40.9 µg/m³ near Charleston.
107.2 µg/m³ peak ≈ 8.3 cigarettes per person 923k people affected
Stagnant pollution mixture over Bakersfield, 2 days, peaking at 107.2 µg/m³ near Bakersfield.
Agency/press 2Reviewed source 2state-local-official-archive-discovery-v1 1
29.8 µg/m³ peak ≈ 1.1 cigarettes per person 1.1M people affected 1 top-ten day
Dust over Tucson, 1 day, peaking at 29.8 µg/m³ near Tucson.
62.3 µg/m³ peak ≈ 2.2 cigarettes per person 11M people affected
Fireworks over 2 metros, 1 day, peaking at 62.3 µg/m³ near Chicago.
EPA AQS 3Agency/press 2
43 µg/m³ peak ≈ 1.4 cigarettes per person 7.8M people affected
Dust over Houston, 1 day, peaking at 43 µg/m³ near Houston.
EPA AQS 1Agency/press 1
44.6 µg/m³ peak ≈ 1.6 cigarettes per person 6.5M people affected
Wildfire smoke over Miami, 1 day, peaking at 44.6 µg/m³ near Miami.
Agency/press 2
34.7 µg/m³ peak ≈ 1.2 cigarettes per person 1.5M people affected
Prescribed fire over Oklahoma City, 1 day, peaking at 34.7 µg/m³ near Oklahoma City.
Reviewed source 1Agency/press 1
50.6 µg/m³ peak ≈ 1.9 cigarettes per person 661k people affected 1 top-ten day
Prescribed fire over Wichita, 1 day, peaking at 50.6 µg/m³ near Wichita.
51.6 µg/m³ peak ≈ 1.7 cigarettes per person 2.2M people affected
Temperature inversion over Indianapolis, 1 day, peaking at 51.6 µg/m³ near Indianapolis.
Reviewed source 3Agency/press 1
57 µg/m³ peak ≈ 2.2 cigarettes per person 3.1M people affected 1 top-ten day
Stagnant pollution mixture over Denver, 1 day, peaking at 57 µg/m³ near Denver.
Reviewed source 1Agency/press 1
43.8 µg/m³ peak ≈ 1.6 cigarettes per person 1.7M people affected
Temperature inversion over Providence, 1 day, peaking at 43.8 µg/m³ near Providence.
Reviewed source 2
101.7 µg/m³ peak ≈ 4.1 cigarettes per person 5.2M people affected 1 top-ten day
Mixed causes over Phoenix, 1 day, peaking at 101.7 µg/m³ near Phoenix.
Agency/press 1state-local-official-archive-discovery-v1 1
72.2 µg/m³ peak ≈ 2.9 cigarettes per person 668k people affected 1 top-ten day
Fireworks over Ogden, 1 day, peaking at 72.2 µg/m³ near Ogden.
68.2 µg/m³ peak ≈ 4.1 cigarettes per person 2.4M people affected 1 top-ten day
Fireworks over Las Vegas, 2 days, peaking at 68.2 µg/m³ near Las Vegas.
114.9 µg/m³ peak ≈ 8.9 cigarettes per person 923k people affected 1 top-ten day
Other over Bakersfield, 2 days, peaking at 114.9 µg/m³ near Bakersfield.
67.7 µg/m³ peak ≈ 5.3 cigarettes per person 2.5M people affected
Stagnant pollution mixture over Portland, 2 days, peaking at 67.7 µg/m³ near Portland.
Reviewed source 2Agency/press 1
55.6 µg/m³ peak ≈ 2.2 cigarettes per person 2.5M people affected
Temperature inversion over Portland, 1 day, peaking at 55.6 µg/m³ near Portland.
Agency/press 1Reviewed source 1
43.4 µg/m³ peak ≈ 1.5 cigarettes per person 8.3M people affected
Dust over Dallas, 1 day, peaking at 43.4 µg/m³ near Dallas.
Reviewed source 2
76.9 µg/m³ peak ≈ 3.2 cigarettes per person 668k people affected 1 top-ten day
Fireworks over Ogden, 1 day, peaking at 76.9 µg/m³ near Ogden.
EPA AQS 2Agency/press 1
78.6 µg/m³ peak ≈ 3.1 cigarettes per person 879k people affected
Dust over El Paso, 1 day, peaking at 78.6 µg/m³ near El Paso.
EPA AQS 1Agency/press 1
75.5 µg/m³ peak ≈ 3.0 cigarettes per person 879k people affected
Dust over El Paso, 1 day, peaking at 75.5 µg/m³ near El Paso.
32.4 µg/m³ peak ≈ 1.2 cigarettes per person 1.1M people affected 1 top-ten day
Dust over Tucson, 1 day, peaking at 32.4 µg/m³ near Tucson.
Reviewed source 2
129.5 µg/m³ peak ≈ 15.5 cigarettes per person 1.4M people affected 1 city record set, 2 top-ten days
Temperature inversion over 2 metros, 7 days, peaking at 129.5 µg/m³ near Provo. 1 metro set an all-time record.
Agency/press 1Reviewed source 2
95.2 µg/m³ peak ≈ 6.0 cigarettes per person 2.7M people affected 2 top-ten days
Temperature inversion over 3 metros, 4 days, peaking at 95.2 µg/m³ near Provo.
Agency/press 1Reviewed source 1
97.3 µg/m³ peak ≈ 3.9 cigarettes per person 5.2M people affected
Fireworks over Phoenix, 1 day, peaking at 97.3 µg/m³ near Phoenix.
Reviewed source 1state-local-official-archive-discovery-v1 1
25.8 µg/m³ peak ≈ 0.9 cigarettes per person 658k people affected
Fireworks over Palm Bay, 1 day, peaking at 25.8 µg/m³ near Palm Bay.
83.3 µg/m³ peak ≈ 3.4 cigarettes per person 2.5M people affected
Wildfire smoke over Sacramento, 1 day, peaking at 83.3 µg/m³ near Sacramento.
83.5 µg/m³ peak ≈ 3.5 cigarettes per person 926k people affected 1 top-ten day
Fireworks over Albuquerque, 1 day, peaking at 83.5 µg/m³ near Albuquerque.
63.7 µg/m³ peak ≈ 2.6 cigarettes per person 668k people affected
Fireworks over Ogden, 1 day, peaking at 63.7 µg/m³ near Ogden.
EPA AQS 1Agency/press 2
Origin: Windblown San Joaquin Valley dust
108.4 µg/m³ peak ≈ 4.3 cigarettes per person 923k people affected
Dust over Bakersfield, 1 day, peaking at 108.4 µg/m³ near Bakersfield. Origin traced to Windblown San Joaquin Valley dust.
Reviewed source 1Agency/press 1
Named source County Line Fire · Northern Florida
82.8 µg/m³ peak ≈ 6.4 cigarettes per person 1.8M people affected 1 top-ten day
Wildfire smoke over Jacksonville, 3 days, peaking at 82.8 µg/m³ near Jacksonville. Origin traced to Northern Florida.
Agency/press 2
77.2 µg/m³ peak ≈ 2.9 cigarettes per person 9.4M people affected 1 top-ten day
Prescribed fire over Chicago, 1 day, peaking at 77.2 µg/m³ near Chicago.
Origin: Northern Mexico
130.4 µg/m³ peak ≈ 5.5 cigarettes per person 879k people affected 1 top-ten day
Dust over El Paso, 1 day, peaking at 130.4 µg/m³ near El Paso. Origin traced to Northern Mexico.
EPA AQS 1Agency/press 2
85 µg/m³ peak ≈ 3.4 cigarettes per person 879k people affected
Dust over El Paso, 1 day, peaking at 85 µg/m³ near El Paso.
EPA AQS 1Agency/press 1
48.9 µg/m³ peak ≈ 1.8 cigarettes per person 870k people affected 1 top-ten day
Prescribed fire over Charleston, 1 day, peaking at 48.9 µg/m³ near Charleston.
23.5 µg/m³ peak ≈ 0.9 cigarettes per person 999k people affected
volcanic_emissions over Urban Honolulu, 1 day, peaking at 23.5 µg/m³ near Urban Honolulu.
Reviewed source 2
112.6 µg/m³ peak ≈ 4.6 cigarettes per person 5.2M people affected 1 top-ten day
Mixed causes over Phoenix, 1 day, peaking at 112.6 µg/m³ near Phoenix.
Reviewed source 1state-local-official-archive-discovery-v1 1
70.7 µg/m³ peak ≈ 2.6 cigarettes per person 3.3M people affected
Fireworks over San Diego, 1 day, peaking at 70.7 µg/m³ near San Diego.
Reviewed source 1
61.2 µg/m³ peak ≈ 2.4 cigarettes per person 2.4M people affected 1 top-ten day
Fireworks over Las Vegas, 1 day, peaking at 61.2 µg/m³ near Las Vegas.
40 µg/m³ peak ≈ 1.4 cigarettes per person 7.3M people affected
Fireworks over 2 metros, 1 day, peaking at 40 µg/m³ near Miami.
67.4 µg/m³ peak ≈ 2.5 cigarettes per person 5.2M people affected
Residential combustion over Phoenix, 1 day, peaking at 67.4 µg/m³ near Phoenix.
Reviewed source 1state-local-official-archive-discovery-v1 1
45.9 µg/m³ peak ≈ 2.9 cigarettes per person 883k people affected
Wildfire smoke over Baton Rouge, 2 days, peaking at 45.9 µg/m³ near Baton Rouge.
EPA AQS 2
41.7 µg/m³ peak ≈ 1.5 cigarettes per person 1.8M people affected
Wildfire smoke over Virginia Beach, 1 day, peaking at 41.7 µg/m³ near Virginia Beach.
Named source Great Dismal Swamp wildfire · Great Dismal Swamp, Virginia and North Carolina
52.9 µg/m³ peak ≈ 2.0 cigarettes per person 1.8M people affected
Wildfire smoke over Virginia Beach, 1 day, peaking at 52.9 µg/m³ near Virginia Beach. Origin traced to Great Dismal Swamp, Virginia and North Carolina.
EPA AQS 1NWS alert 1Agency/press 1
Cited: Virginia Department of Environmental Quality
102.3 µg/m³ peak ≈ 4.1 cigarettes per person 5.2M people affected 1 top-ten day
Dust over Phoenix, 1 day, peaking at 102.3 µg/m³ near Phoenix.
EPA AQS 2NWS record 1Agency/press 2
65.2 µg/m³ peak ≈ 4.1 cigarettes per person 12M people affected
Fireworks over 2 metros, 2 days, peaking at 65.2 µg/m³ near Chicago.
Named source Honey Prairie Fire · Southeastern Georgia
42.6 µg/m³ peak ≈ 4.4 cigarettes per person 870k people affected
Wildfire smoke over Charleston, 3 days, peaking at 42.6 µg/m³ near Charleston. Origin traced to Southeastern Georgia.
EPA AQS 3Agency/press 1
47.5 µg/m³ peak ≈ 1.8 cigarettes per person 870k people affected 1 top-ten day
Wildfire smoke over Charleston, 1 day, peaking at 47.5 µg/m³ near Charleston.
39.9 µg/m³ peak ≈ 1.4 cigarettes per person 6.5M people affected
Wildfire smoke over Miami, 1 day, peaking at 39.9 µg/m³ near Miami.
58.2 µg/m³ peak ≈ 4.4 cigarettes per person 886k people affected
Wildfire smoke over Allentown, 2 days, peaking at 58.2 µg/m³ near Allentown.
39.7 µg/m³ peak ≈ 1.5 cigarettes per person 926k people affected
Wildfire smoke over Albuquerque, 1 day, peaking at 39.7 µg/m³ near Albuquerque.
91.7 µg/m³ peak ≈ 5.5 cigarettes per person 6.5M people affected 1 city record set
Wildfire smoke over Miami, 2 days, peaking at 91.7 µg/m³ near Miami. 1 metro set an all-time record.
Named source Wallow Fire, Horseshoe Fire · Arizona
53.3 µg/m³ peak ≈ 5.4 cigarettes per person 926k people affected 1 top-ten day
Wildfire smoke over Albuquerque, 3 days, peaking at 53.3 µg/m³ near Albuquerque. Origin traced to Arizona.
EPA AQS 5Agency/press 1
53.3 µg/m³ peak ≈ 3.5 cigarettes per person 997k people affected 1 top-ten day
Wildfire smoke over Greenville, 2 days, peaking at 53.3 µg/m³ near Greenville.
38.2 µg/m³ peak ≈ 1.3 cigarettes per person 606k people affected
Mixed causes over Jackson, 1 day, peaking at 38.2 µg/m³ near Jackson.
Reviewed source 4
56.6 µg/m³ peak ≈ 2.2 cigarettes per person 668k people affected
Temperature inversion over Ogden, 1 day, peaking at 56.6 µg/m³ near Ogden.
64.6 µg/m³ peak ≈ 4.9 cigarettes per person 668k people affected
Winter inversion over Ogden, 2 days, peaking at 64.6 µg/m³ near Ogden.
99.1 µg/m³ peak ≈ 3.9 cigarettes per person 5.2M people affected 1 top-ten day
Fireworks over Phoenix, 1 day, peaking at 99.1 µg/m³ near Phoenix.
state-local-official-archive-discovery-v1 1
55.6 µg/m³ peak ≈ 1.9 cigarettes per person 6.9M people affected
Fireworks over 2 metros, 1 day, peaking at 55.6 µg/m³ near Philadelphia.
57.5 µg/m³ peak ≈ 2.8 cigarettes per person 2.3M people affected 1 top-ten day
Winter inversion over 3 metros, 2 days, peaking at 57.5 µg/m³ near Bridgeport.
NWS alert 1Agency/press 1
30 µg/m³ peak ≈ 1.2 cigarettes per person 999k people affected
Fireworks over Urban Honolulu, 1 day, peaking at 30 µg/m³ near Urban Honolulu.
64.8 µg/m³ peak ≈ 2.3 cigarettes per person 6.3M people affected
Temperature inversion over Philadelphia, 1 day, peaking at 64.8 µg/m³ near Philadelphia.
Reviewed source 3
82.6 µg/m³ peak ≈ 3.2 cigarettes per person 5.2M people affected
Residential combustion over Phoenix, 1 day, peaking at 82.6 µg/m³ near Phoenix.
Reviewed source 1Agency/press 1state-local-official-archive-discovery-v1 1
56.2 µg/m³ peak ≈ 2.2 cigarettes per person 1.7M people affected 1 top-ten day
Fireworks over Providence, 1 day, peaking at 56.2 µg/m³ near Providence.
44.6 µg/m³ peak ≈ 1.6 cigarettes per person 1.0M people affected
Fireworks over Omaha, 1 day, peaking at 44.6 µg/m³ near Omaha.
41.9 µg/m³ peak ≈ 1.5 cigarettes per person 2.4M people affected
Fireworks over Las Vegas, 1 day, peaking at 41.9 µg/m³ near Las Vegas.
40.5 µg/m³ peak ≈ 1.4 cigarettes per person 997k people affected
Fireworks over Greenville, 1 day, peaking at 40.5 µg/m³ near Greenville.
Origin: Canada
60.5 µg/m³ peak ≈ 2.3 cigarettes per person 5.0M people affected 1 top-ten day
Wildfire smoke over Boston, 1 day, peaking at 60.5 µg/m³ near Boston. Origin traced to Canada.
EPA AQS 2
107.8 µg/m³ peak ≈ 4.3 cigarettes per person 923k people affected
Dust over Bakersfield, 1 day, peaking at 107.8 µg/m³ near Bakersfield.
EPA AQS 2Agency/press 1
41.1 µg/m³ peak ≈ 1.5 cigarettes per person 1.2M people affected
Wildfire smoke over Buffalo, 1 day, peaking at 41.1 µg/m³ near Buffalo.
43 µg/m³ peak ≈ 1.6 cigarettes per person 708k people affected
Stagnant pollution mixture over Madison, 1 day, peaking at 43 µg/m³ near Madison.
45.2 µg/m³ peak ≈ 1.7 cigarettes per person 708k people affected
Temperature inversion over Madison, 1 day, peaking at 45.2 µg/m³ near Madison.
Reviewed source 1
Origin: Kilauea volcanic emissions
29.9 µg/m³ peak ≈ 1.1 cigarettes per person 999k people affected
volcanic_emissions over Urban Honolulu, 1 day, peaking at 29.9 µg/m³ near Urban Honolulu. Origin traced to Kilauea volcanic emissions.
Reviewed source 2
43 µg/m³ peak ≈ 1.5 cigarettes per person 2.3M people affected
Stagnant pollution mixture over Kansas City, 1 day, peaking at 43 µg/m³ near Kansas City.
Reviewed source 2
76.7 µg/m³ peak ≈ 6.6 cigarettes per person 2.0M people affected
Temperature inversion over 2 metros, 3 days, peaking at 76.7 µg/m³ near Salt Lake City.
Reviewed source 1Agency/press 1
50 µg/m³ peak ≈ 1.9 cigarettes per person 1.0M people affected 1 top-ten day
Stagnant pollution mixture over Omaha, 1 day, peaking at 50 µg/m³ near Omaha.
Reviewed source 4
41.9 µg/m³ peak ≈ 1.5 cigarettes per person 6.5M people affected
Fireworks over Miami, 1 day, peaking at 41.9 µg/m³ near Miami.
27.6 µg/m³ peak ≈ 1.0 cigarettes per person 999k people affected
Fireworks over Urban Honolulu, 1 day, peaking at 27.6 µg/m³ near Urban Honolulu.
43.4 µg/m³ peak ≈ 1.5 cigarettes per person 966k people affected 1 top-ten day
Fireworks over New Orleans, 1 day, peaking at 43.4 µg/m³ near New Orleans.
47 µg/m³ peak ≈ 1.6 cigarettes per person 1.8M people affected
Stagnant pollution mixture over 2 metros, 1 day, peaking at 47 µg/m³ near Omaha.
Agency/press 1Reviewed source 1
Origin: Kilauea volcanic emissions
25.6 µg/m³ peak ≈ 1.0 cigarettes per person 999k people affected
volcanic_emissions over Urban Honolulu, 1 day, peaking at 25.6 µg/m³ near Urban Honolulu. Origin traced to Kilauea volcanic emissions.
Reviewed source 2
56.2 µg/m³ peak ≈ 2.3 cigarettes per person 2.5M people affected
Temperature inversion over Portland, 1 day, peaking at 56.2 µg/m³ near Portland.
Agency/press 1Reviewed source 1 1
54.2 µg/m³ peak ≈ 1.9 cigarettes per person 20M people affected
Stagnant pollution mixture over New York, 1 day, peaking at 54.2 µg/m³ near New York.
Reviewed source 3
23.1 µg/m³ peak ≈ 0.8 cigarettes per person 999k people affected
Other over Urban Honolulu, 1 day, peaking at 23.1 µg/m³ near Urban Honolulu.
51.1 µg/m³ peak ≈ 1.9 cigarettes per person 1.6M people affected
Regional secondary PM over Milwaukee, 1 day, peaking at 51.1 µg/m³ near Milwaukee.
Reviewed source 2Agency/press 1
Origin: Wasatch Front, Utah
80.4 µg/m³ peak ≈ 6.6 cigarettes per person 2.7M people affected
Winter inversion over 3 metros, 4 days, peaking at 80.4 µg/m³ near Provo. Origin traced to Wasatch Front, Utah.
Agency/press 1
78.3 µg/m³ peak ≈ 3.0 cigarettes per person 3.3M people affected 1 top-ten day
Fireworks over San Diego, 1 day, peaking at 78.3 µg/m³ near San Diego.
71.3 µg/m³ peak ≈ 2.7 cigarettes per person 5.2M people affected
Fireworks over Phoenix, 1 day, peaking at 71.3 µg/m³ near Phoenix.
Reviewed source 2state-local-official-archive-discovery-v1 1
49.3 µg/m³ peak ≈ 1.8 cigarettes per person 2.4M people affected
Fireworks over Las Vegas, 1 day, peaking at 49.3 µg/m³ near Las Vegas.
78.3 µg/m³ peak ≈ 2.9 cigarettes per person 13M people affected
Wildfire smoke over Los Angeles, 1 day, peaking at 78.3 µg/m³ near Los Angeles.
70.7 µg/m³ peak ≈ 2.8 cigarettes per person 1.8M people affected 1 top-ten day
Wildfire smoke over Virginia Beach, 1 day, peaking at 70.7 µg/m³ near Virginia Beach.
EPA AQS 1Agency/press 1
84.9 µg/m³ peak ≈ 5.6 cigarettes per person 1.8M people affected 1 top-ten day
Wildfire smoke over Virginia Beach, 2 days, peaking at 84.9 µg/m³ near Virginia Beach.
EPA AQS 2Agency/press 2
81.2 µg/m³ peak ≈ 3.2 cigarettes per person 816k people affected
Wildfire smoke over Stockton, 1 day, peaking at 81.2 µg/m³ near Stockton.
EPA AQS 1Agency/press 1
Named source South One Fire, Evans Road Fire · eastern North Carolina; southeastern Virginia
99 µg/m³ peak ≈ 4.3 cigarettes per person 12M people affected 3 city records set, 5 top-ten days
Wildfire smoke over 6 metros, 14 days, peaking at 99 µg/m³ near Raleigh. 3 metros set an all-time record. Origin traced to eastern North Carolina; southeastern Virginia.
EPA AQS 13Agency/press 5
48.9 µg/m³ peak ≈ 1.8 cigarettes per person 1.4M people affected 1 top-ten day
Wildfire smoke over Richmond, 1 day, peaking at 48.9 µg/m³ near Richmond.
34.6 µg/m³ peak ≈ 1.4 cigarettes per person 999k people affected
volcanic_emissions over Urban Honolulu, 1 day, peaking at 34.6 µg/m³ near Urban Honolulu.
44.5 µg/m³ peak ≈ 1.7 cigarettes per person 1.8M people affected
Wildfire smoke over Virginia Beach, 1 day, peaking at 44.5 µg/m³ near Virginia Beach.
55.8 µg/m³ peak ≈ 2.0 cigarettes per person 1.5M people affected 1 top-ten day
Temperature inversion over 2 metros, 1 day, peaking at 55.8 µg/m³ near Bridgeport.
50.8 µg/m³ peak ≈ 1.9 cigarettes per person 464k people affected
Stagnant pollution mixture over Springfield, 1 day, peaking at 50.8 µg/m³ near Springfield.
Reviewed source 2
29.5 µg/m³ peak ≈ 1.1 cigarettes per person 999k people affected
Other over Urban Honolulu, 1 day, peaking at 29.5 µg/m³ near Urban Honolulu.
54 µg/m³ peak ≈ 2.0 cigarettes per person 966k people affected 1 top-ten day
Fireworks over New Orleans, 1 day, peaking at 54 µg/m³ near New Orleans.
Origin: Minnesota Twin Cities region
53.7 µg/m³ peak ≈ 2.0 cigarettes per person 3.8M people affected
Winter inversion over Minneapolis, 1 day, peaking at 53.7 µg/m³ near Minneapolis. Origin traced to Minnesota Twin Cities region.
61.6 µg/m³ peak ≈ 3.1 cigarettes per person 2.3M people affected 1 top-ten day
Stagnant pollution mixture over 2 metros, 3 days, peaking at 61.6 µg/m³ near Madison.
82.8 µg/m³ peak ≈ 3.1 cigarettes per person 13M people affected
Temperature inversion over Los Angeles, 1 day, peaking at 82.8 µg/m³ near Los Angeles.
Reviewed source 3
Origin: Southern California
126.2 µg/m³ peak ≈ 13.2 cigarettes per person 3.3M people affected 1 top-ten day
Wildfire smoke over San Diego, 4 days, peaking at 126.2 µg/m³ near San Diego. Origin traced to Southern California.
EPA AQS 3Agency/press 3
Cited: City of San Diego
35.3 µg/m³ peak ≈ 1.3 cigarettes per person 740k people affected 1 top-ten day
Wildfire smoke over Deltona, 1 day, peaking at 35.3 µg/m³ near Deltona.
55.2 µg/m³ peak ≈ 2.0 cigarettes per person 20M people affected
Regional secondary PM over New York, 1 day, peaking at 55.2 µg/m³ near New York.
62.4 µg/m³ peak ≈ 2.3 cigarettes per person 958k people affected 1 top-ten day
Regional secondary PM over Knoxville, 1 day, peaking at 62.4 µg/m³ near Knoxville.
Reviewed source 2
43.2 µg/m³ peak ≈ 1.5 cigarettes per person 1.4M people affected
Regional secondary PM over Richmond, 1 day, peaking at 43.2 µg/m³ near Richmond.
Reviewed source 1
51.2 µg/m³ peak ≈ 3.5 cigarettes per person 1.5M people affected 1 top-ten day
Wildfire smoke over 2 metros, 3 days, peaking at 51.2 µg/m³ near Charleston.
EPA AQS 3
Origin: Idaho, Montana, and Canada
46.4 µg/m³ peak ≈ 1.6 cigarettes per person 2.9M people affected 1 top-ten day
Wildfire smoke over 3 metros, 1 day, peaking at 46.4 µg/m³ near Richmond. Origin traced to Idaho, Montana, and Canada.
EPA AQS 1Agency/press 1
51.3 µg/m³ peak ≈ 1.8 cigarettes per person 1.4M people affected
Wildfire smoke over Louisville/Jefferson County, 1 day, peaking at 51.3 µg/m³ near Louisville/Jefferson County.
50.4 µg/m³ peak ≈ 3.3 cigarettes per person 2.8M people affected
Stagnant pollution mixture over St. Louis, 2 days, peaking at 50.4 µg/m³ near St. Louis.
Reviewed source 3
50.2 µg/m³ peak ≈ 3.2 cigarettes per person 3.5M people affected 1 top-ten day
Wildfire smoke over 2 metros, 3 days, peaking at 50.2 µg/m³ near Louisville/Jefferson County.
EPA AQS 4
38.5 µg/m³ peak ≈ 2.5 cigarettes per person 1.1M people affected
Stagnant pollution mixture over Tulsa, 2 days, peaking at 38.5 µg/m³ near Tulsa.
Reviewed source 4
46.6 µg/m³ peak ≈ 1.6 cigarettes per person 2.2M people affected 1 top-ten day
Wildfire smoke over Nashville, 1 day, peaking at 46.6 µg/m³ near Nashville.
Origin: Salt Lake City, Utah
78.2 µg/m³ peak ≈ 3.2 cigarettes per person 1.3M people affected
Fireworks over Salt Lake City, 1 day, peaking at 78.2 µg/m³ near Salt Lake City. Origin traced to Salt Lake City, Utah.
Agency/press 1
59.2 µg/m³ peak ≈ 4.1 cigarettes per person 6.5M people affected 1 top-ten day
Mixed causes over Miami, 2 days, peaking at 59.2 µg/m³ near Miami.
EPA AQS 3
50.8 µg/m³ peak ≈ 1.9 cigarettes per person 1.2M people affected 1 top-ten day
Fireworks over Buffalo, 1 day, peaking at 50.8 µg/m³ near Buffalo.
50.2 µg/m³ peak ≈ 1.8 cigarettes per person 7.9M people affected
Stagnant pollution mixture over 3 metros, 1 day, peaking at 50.2 µg/m³ near Boston.
Reviewed source 2
45 µg/m³ peak ≈ 1.6 cigarettes per person 1.6M people affected 1 top-ten day
Prescribed fire over Raleigh, 1 day, peaking at 45 µg/m³ near Raleigh.
38.1 µg/m³ peak ≈ 1.2 cigarettes per person 769k people affected
Wildfire smoke over Little Rock, 1 day, peaking at 38.1 µg/m³ near Little Rock.
50.4 µg/m³ peak ≈ 4.8 cigarettes per person 1.3M people affected 1 top-ten day
Wildfire smoke over Memphis, 3 days, peaking at 50.4 µg/m³ near Memphis.
EPA AQS 3
26.2 µg/m³ peak ≈ 0.9 cigarettes per person 935k people affected
Wildfire smoke over North Port, 1 day, peaking at 26.2 µg/m³ near North Port.
87.9 µg/m³ peak ≈ 3.8 cigarettes per person 2.5M people affected 1 city record set, 2 top-ten days
Wildfire smoke over 2 metros, 2 days, peaking at 87.9 µg/m³ near Jacksonville. 1 metro set an all-time record.
EPA AQS 3Agency/press 2
71.5 µg/m³ peak ≈ 2.9 cigarettes per person 870k people affected 1 top-ten day
Wildfire smoke over Charleston, 1 day, peaking at 71.5 µg/m³ near Charleston.
Origin: Ware County, Georgia and northern Florida
137.3 µg/m³ peak ≈ 6.6 cigarettes per person 29M people affected 4 city records set, 9 top-ten days
Wildfire smoke over 13 metros, 25 days, peaking at 137.3 µg/m³ near Tampa. 4 metros set an all-time record. Origin traced to Ware County, Georgia and northern Florida.
EPA AQS 33Agency/press 8
53.9 µg/m³ peak ≈ 3.7 cigarettes per person 6.5M people affected 1 top-ten day
Wildfire smoke over Miami, 2 days, peaking at 53.9 µg/m³ near Miami.
EPA AQS 2Agency/press 2
48.9 µg/m³ peak ≈ 1.7 cigarettes per person 2.5M people affected 1 top-ten day
Wildfire smoke over 2 metros, 1 day, peaking at 48.9 µg/m³ near Jacksonville.
39.2 µg/m³ peak ≈ 1.3 cigarettes per person 870k people affected
Wildfire smoke over Columbia, 1 day, peaking at 39.2 µg/m³ near Columbia.
35.8 µg/m³ peak ≈ 1.1 cigarettes per person 4.7M people affected
Wildfire smoke over 3 metros, 1 day, peaking at 35.8 µg/m³ near Orlando.
EPA AQS 3
39.4 µg/m³ peak ≈ 1.4 cigarettes per person 1.8M people affected
Wildfire smoke over Jacksonville, 1 day, peaking at 39.4 µg/m³ near Jacksonville.
EPA AQS 1Agency/press 1
65.5 µg/m³ peak ≈ 4.9 cigarettes per person 1.8M people affected 1 top-ten day
Wildfire smoke over Jacksonville, 2 days, peaking at 65.5 µg/m³ near Jacksonville.
24 µg/m³ peak ≈ 0.8 cigarettes per person 740k people affected
Wildfire smoke over Deltona, 1 day, peaking at 24 µg/m³ near Deltona.
60.5 µg/m³ peak ≈ 2.4 cigarettes per person 3.1M people affected 1 top-ten day
Temperature inversion over Denver, 1 day, peaking at 60.5 µg/m³ near Denver.
Reviewed source 1
86.6 µg/m³ peak ≈ 11.0 cigarettes per person 2.7M people affected 2 top-ten days
Temperature inversion over 3 metros, 5 days, peaking at 86.6 µg/m³ near Salt Lake City.
Reviewed source 3Agency/press 2
71.6 µg/m³ peak ≈ 2.9 cigarettes per person 4.1M people affected
Residential combustion over Seattle, 1 day, peaking at 71.6 µg/m³ near Seattle.
51.1 µg/m³ peak ≈ 2.1 cigarettes per person 999k people affected
Fireworks over Urban Honolulu, 1 day, peaking at 51.1 µg/m³ near Urban Honolulu.
EPA AQS 1Agency/press 1
46.6 µg/m³ peak ≈ 1.8 cigarettes per person 926k people affected 1 top-ten day
Fireworks over Albuquerque, 1 day, peaking at 46.6 µg/m³ near Albuquerque.
75.3 µg/m³ peak ≈ 2.8 cigarettes per person 6.6M people affected
Residential combustion over 2 metros, 1 day, peaking at 75.3 µg/m³ near San Francisco.
Agency/press 1Reviewed source 4
68.3 µg/m³ peak ≈ 2.7 cigarettes per person 4.1M people affected
Residential combustion over Seattle, 1 day, peaking at 68.3 µg/m³ near Seattle.
63.3 µg/m³ peak ≈ 2.3 cigarettes per person 3.3M people affected
Temperature inversion over San Diego, 1 day, peaking at 63.3 µg/m³ near San Diego.
Reviewed source 4Agency/press 1
39.1 µg/m³ peak ≈ 1.3 cigarettes per person 588k people affected
Stagnant pollution mixture over Chattanooga, 1 day, peaking at 39.1 µg/m³ near Chattanooga.
Reviewed source 3
41.4 µg/m³ peak ≈ 1.5 cigarettes per person 966k people affected
Other over New Orleans, 1 day, peaking at 41.4 µg/m³ near New Orleans.
44.2 µg/m³ peak ≈ 1.4 cigarettes per person 7.8M people affected
Dust over Houston, 1 day, peaking at 44.2 µg/m³ near Houston.
43.7 µg/m³ peak ≈ 1.6 cigarettes per person 1.8M people affected
Stagnant pollution mixture over Virginia Beach, 1 day, peaking at 43.7 µg/m³ near Virginia Beach.
41.1 µg/m³ peak ≈ 1.4 cigarettes per person 3.0M people affected
Stagnant pollution mixture over 3 metros, 2 days, peaking at 41.1 µg/m³ near Raleigh.
48.9 µg/m³ peak ≈ 1.7 cigarettes per person 1.4M people affected
Fireworks over Louisville/Jefferson County, 1 day, peaking at 48.9 µg/m³ near Louisville/Jefferson County.
63 µg/m³ peak ≈ 2.3 cigarettes per person 6.3M people affected
Regional secondary PM over Philadelphia, 1 day, peaking at 63 µg/m³ near Philadelphia.
Reviewed source 2
75.8 µg/m³ peak ≈ 2.9 cigarettes per person 6.4M people affected 1 top-ten day
Prescribed fire over Washington, 1 day, peaking at 75.8 µg/m³ near Washington.
53.2 µg/m³ peak ≈ 1.7 cigarettes per person 3.3M people affected
Fireworks over 3 metros, 1 day, peaking at 53.2 µg/m³ near New Haven.
49.2 µg/m³ peak ≈ 1.8 cigarettes per person 588k people affected
Mixed causes over Chattanooga, 1 day, peaking at 49.2 µg/m³ near Chattanooga.
48.5 µg/m³ peak ≈ 1.8 cigarettes per person 2.4M people affected
Fireworks over Las Vegas, 1 day, peaking at 48.5 µg/m³ near Las Vegas.
43.3 µg/m³ peak ≈ 1.5 cigarettes per person 705k people affected
Fireworks over Winston, 1 day, peaking at 43.3 µg/m³ near Winston.
Origin: Smoldering east-central Florida brush fires
28 µg/m³ peak ≈ 1.0 cigarettes per person 658k people affected 1 top-ten day
Wildfire smoke over Palm Bay, 1 day, peaking at 28 µg/m³ near Palm Bay. Origin traced to Smoldering east-central Florida brush fires.
Reviewed source 4
Origin: Smoldering east-central Florida wildfires
36 µg/m³ peak ≈ 1.4 cigarettes per person 658k people affected 1 top-ten day
Wildfire smoke over Palm Bay, 1 day, peaking at 36 µg/m³ near Palm Bay. Origin traced to Smoldering east-central Florida wildfires.
Reviewed source 3
38.9 µg/m³ peak ≈ 1.2 cigarettes per person 7.8M people affected
Wildfire smoke over Houston, 1 day, peaking at 38.9 µg/m³ near Houston.
34.7 µg/m³ peak ≈ 0.9 cigarettes per person 2.4M people affected 1 top-ten day
Wildfire smoke over 3 metros, 1 day, peaking at 34.7 µg/m³ near Palm Bay.
34.8 µg/m³ peak ≈ 1.2 cigarettes per person 2.9M people affected
Fireworks over Orlando, 1 day, peaking at 34.8 µg/m³ near Orlando.
Reviewed source 1
88.1 µg/m³ peak ≈ 3.8 cigarettes per person 999k people affected 1 top-ten day
Fireworks over Urban Honolulu, 1 day, peaking at 88.1 µg/m³ near Urban Honolulu.
EPA AQS 1Agency/press 1
65.3 µg/m³ peak ≈ 2.7 cigarettes per person 2.5M people affected
Regional secondary PM over Portland, 1 day, peaking at 65.3 µg/m³ near Portland.
61 µg/m³ peak ≈ 2.5 cigarettes per person 2.5M people affected
Regional secondary PM over Portland, 1 day, peaking at 61 µg/m³ near Portland.
Reviewed source 2
59.2 µg/m³ peak ≈ 2.3 cigarettes per person 966k people affected 1 top-ten day
Other over New Orleans, 1 day, peaking at 59.2 µg/m³ near New Orleans.
40.5 µg/m³ peak ≈ 2.6 cigarettes per person 769k people affected
Prescribed fire over Little Rock, 2 days, peaking at 40.5 µg/m³ near Little Rock.
Reviewed source 3
106.2 µg/m³ peak ≈ 10.6 cigarettes per person 4.7M people affected 1 top-ten day
Stagnant pollution mixture over Riverside, 3 days, peaking at 106.2 µg/m³ near Riverside.
Reviewed source 2
40.5 µg/m³ peak ≈ 1.3 cigarettes per person 3.8M people affected
Prescribed fire over 2 metros, 2 days, peaking at 40.5 µg/m³ near Charlotte.
EPA AQS 2
61.1 µg/m³ peak ≈ 2.3 cigarettes per person 2.2M people affected 1 city record set
Prescribed fire over Nashville, 1 day, peaking at 61.1 µg/m³ near Nashville. 1 metro set an all-time record.
Reviewed source 1 1
44.8 µg/m³ peak ≈ 1.6 cigarettes per person 966k people affected 1 top-ten day
Other over New Orleans, 1 day, peaking at 44.8 µg/m³ near New Orleans.
45 µg/m³ peak ≈ 1.7 cigarettes per person 1.2M people affected
Stagnant pollution mixture over Buffalo, 1 day, peaking at 45 µg/m³ near Buffalo.
Reviewed source 4
44.7 µg/m³ peak ≈ 1.7 cigarettes per person 861k people affected 1 city record set
Temperature inversion over Cape Coral, 1 day, peaking at 44.7 µg/m³ near Cape Coral. 1 metro set an all-time record.
42.9 µg/m³ peak ≈ 1.6 cigarettes per person 935k people affected 1 top-ten day
Temperature inversion over North Port, 1 day, peaking at 42.9 µg/m³ near North Port.
42.2 µg/m³ peak ≈ 4.4 cigarettes per person 870k people affected
Stagnant pollution mixture over Charleston, 3 days, peaking at 42.2 µg/m³ near Charleston.
Reviewed source 2
46.8 µg/m³ peak ≈ 5.4 cigarettes per person 10M people affected 5 top-ten days
Dust over 6 metros, 5 days, peaking at 46.8 µg/m³ near Jacksonville.
EPA AQS 3
84.9 µg/m³ peak ≈ 4.0 cigarettes per person 4.3M people affected 1 top-ten day
Mixed causes over 3 metros, 2 days, peaking at 84.9 µg/m³ near Pittsburgh.
Reviewed source 2Agency/press 1
52.5 µg/m³ peak ≈ 1.8 cigarettes per person 6.4M people affected
Mixed causes over Atlanta, 1 day, peaking at 52.5 µg/m³ near Atlanta.
Reviewed source 3
Origin: Idaho and Montana fire smoke
48.2 µg/m³ peak ≈ 1.6 cigarettes per person 4.7M people affected
Mixed causes over 5 metros, 1 day, peaking at 48.2 µg/m³ near Bridgeport. Origin traced to Idaho and Montana fire smoke.
Reviewed source 7Agency/press 1
Origin: Idaho and Montana wildfire smoke
42.8 µg/m³ peak ≈ 1.6 cigarettes per person 913k people affected
Mixed causes over Albany, 1 day, peaking at 42.8 µg/m³ near Albany. Origin traced to Idaho and Montana wildfire smoke.
Reviewed source 5
42.7 µg/m³ peak ≈ 1.5 cigarettes per person 2.2M people affected
Temperature inversion over Nashville, 1 day, peaking at 42.7 µg/m³ near Nashville.
Reviewed source 1Agency/press 1
63 µg/m³ peak ≈ 4.4 cigarettes per person 1.2M people affected 1 top-ten day
Stagnant pollution mixture over Birmingham, 2 days, peaking at 63 µg/m³ near Birmingham.
Reviewed source 3
37.6 µg/m³ peak ≈ 1.2 cigarettes per person 606k people affected
Temperature inversion over Jackson, 1 day, peaking at 37.6 µg/m³ near Jackson.
Origin: Idaho and Montana
58.9 µg/m³ peak ≈ 3.6 cigarettes per person 11M people affected 3 top-ten days
Wildfire smoke over 7 metros, 5 days, peaking at 58.9 µg/m³ near Cincinnati. Origin traced to Idaho and Montana.
EPA AQS 3Agency/press 4
42.4 µg/m³ peak ≈ 1.5 cigarettes per person 1.7M people affected
Stagnant pollution mixture over Providence, 1 day, peaking at 42.4 µg/m³ near Providence.
Reviewed source 1
49.3 µg/m³ peak ≈ 1.8 cigarettes per person 577k people affected
Stagnant pollution mixture over New Haven, 1 day, peaking at 49.3 µg/m³ near New Haven.
Reviewed source 1
42.1 µg/m³ peak ≈ 1.5 cigarettes per person 5.0M people affected
Stagnant pollution mixture over Boston, 1 day, peaking at 42.1 µg/m³ near Boston.
Reviewed source 1
49.9 µg/m³ peak ≈ 1.8 cigarettes per person 2.9M people affected
Stagnant pollution mixture over Baltimore, 1 day, peaking at 49.9 µg/m³ near Baltimore.
Reviewed source 3
39 µg/m³ peak ≈ 1.4 cigarettes per person 801k people affected
Other over Greensboro, 1 day, peaking at 39 µg/m³ near Greensboro.
44.9 µg/m³ peak ≈ 1.5 cigarettes per person 2.9M people affected 1 top-ten day
Regional secondary PM over Charlotte, 1 day, peaking at 44.9 µg/m³ near Charlotte.
Reviewed source 4
41.5 µg/m³ peak ≈ 1.3 cigarettes per person 4.6M people affected
Regional secondary PM over 4 metros, 1 day, peaking at 41.5 µg/m³ near Winston.
Reviewed source 1
30.9 µg/m³ peak ≈ 1.1 cigarettes per person 853k people affected 1 top-ten day
Dust over Lakeland, 1 day, peaking at 30.9 µg/m³ near Lakeland.
63 µg/m³ peak ≈ 2.3 cigarettes per person 1.2M people affected 1 top-ten day
Stagnant pollution mixture over Birmingham, 1 day, peaking at 63 µg/m³ near Birmingham.
Reviewed source 3 1
45.2 µg/m³ peak ≈ 2.0 cigarettes per person 2.4M people affected 1 top-ten day
Stagnant pollution mixture over 3 metros, 2 days, peaking at 45.2 µg/m³ near Augusta.
79.8 µg/m³ peak ≈ 2.9 cigarettes per person 4.7M people affected
Fireworks over Riverside, 1 day, peaking at 79.8 µg/m³ near Riverside.
36.3 µg/m³ peak ≈ 1.3 cigarettes per person 926k people affected
Fireworks over Albuquerque, 1 day, peaking at 36.3 µg/m³ near Albuquerque.
79.2 µg/m³ peak ≈ 2.3 cigarettes per person 11M people affected 2 top-ten days
Other over 6 metros, 1 day, peaking at 79.2 µg/m³ near Detroit.
Agency/press 1
46.9 µg/m³ peak ≈ 1.7 cigarettes per person 5.0M people affected
Regional secondary PM over Boston, 1 day, peaking at 46.9 µg/m³ near Boston.
Reviewed source 2
46.5 µg/m³ peak ≈ 1.6 cigarettes per person 2.2M people affected 1 top-ten day
Regional secondary PM over Nashville, 1 day, peaking at 46.5 µg/m³ near Nashville.
49.4 µg/m³ peak ≈ 1.8 cigarettes per person 606k people affected 1 city record set
Regional secondary PM over Jackson, 1 day, peaking at 49.4 µg/m³ near Jackson. 1 metro set an all-time record.
Agency/press 1Reviewed source 2
Origin: Eastern U.S. regional haze mixture
77.8 µg/m³ peak ≈ 4.1 cigarettes per person 4.5M people affected 1 top-ten day
Mixed causes over 3 metros, 6 days, peaking at 77.8 µg/m³ near Pittsburgh. Origin traced to Eastern U.S. regional haze mixture.
Agency/press 1Reviewed source 2
43.1 µg/m³ peak ≈ 1.5 cigarettes per person 2.2M people affected
Stagnant pollution mixture over Nashville, 1 day, peaking at 43.1 µg/m³ near Nashville.
44.9 µg/m³ peak ≈ 3.2 cigarettes per person 3.3M people affected 1 top-ten day
Mixed causes over 4 metros, 5 days, peaking at 44.9 µg/m³ near Augusta.
69.6 µg/m³ peak ≈ 2.5 cigarettes per person 2.4M people affected
Regional secondary PM over Pittsburgh, 1 day, peaking at 69.6 µg/m³ near Pittsburgh.
46.4 µg/m³ peak ≈ 1.7 cigarettes per person 661k people affected 1 top-ten day
Wildfire smoke over Wichita, 1 day, peaking at 46.4 µg/m³ near Wichita.
Reviewed source 3
47.1 µg/m³ peak ≈ 1.8 cigarettes per person 1.2M people affected 1 top-ten day
Temperature inversion over Buffalo, 1 day, peaking at 47.1 µg/m³ near Buffalo.
Reviewed source 4
37.6 µg/m³ peak ≈ 1.4 cigarettes per person 1.1M people affected
Temperature inversion over Rochester, 1 day, peaking at 37.6 µg/m³ near Rochester.
Reviewed source 1
81.6 µg/m³ peak ≈ 5.1 cigarettes per person 34M people affected 7 top-ten days
Other over 14 metros, 8 days, peaking at 81.6 µg/m³ near Detroit.
Agency/press 1
40 µg/m³ peak ≈ 1.3 cigarettes per person 7.8M people affected
Regional secondary PM over Houston, 1 day, peaking at 40 µg/m³ near Houston.
44.3 µg/m³ peak ≈ 1.5 cigarettes per person 705k people affected
Stagnant pollution mixture over Winston, 1 day, peaking at 44.3 µg/m³ near Winston.
Reviewed source 3
51.3 µg/m³ peak ≈ 1.6 cigarettes per person 3.4M people affected 2 top-ten days
Fireworks over 4 metros, 2 days, peaking at 51.3 µg/m³ near Greenville.
Reviewed source 1
102.8 µg/m³ peak ≈ 6.7 cigarettes per person 999k people affected 1 top-ten day
Fireworks over Urban Honolulu, 2 days, peaking at 102.8 µg/m³ near Urban Honolulu.
EPA AQS 2Agency/press 2
44.7 µg/m³ peak ≈ 1.7 cigarettes per person 708k people affected
Temperature inversion over Madison, 1 day, peaking at 44.7 µg/m³ near Madison.
Reviewed source 1
69.9 µg/m³ peak ≈ 2.5 cigarettes per person 2.4M people affected
Stagnant pollution mixture over Pittsburgh, 1 day, peaking at 69.9 µg/m³ near Pittsburgh.
Reviewed source 2
82.2 µg/m³ peak ≈ 3.1 cigarettes per person 2.4M people affected 1 top-ten day
Industrial over Pittsburgh, 1 day, peaking at 82.2 µg/m³ near Pittsburgh.
Reviewed source 4
56.1 µg/m³ peak ≈ 2.0 cigarettes per person 958k people affected
Regional secondary PM over Knoxville, 1 day, peaking at 56.1 µg/m³ near Knoxville.
41.7 µg/m³ peak ≈ 1.4 cigarettes per person 1.6M people affected
Temperature inversion over Raleigh, 1 day, peaking at 41.7 µg/m³ near Raleigh.
Reviewed source 3
43.6 µg/m³ peak ≈ 1.4 cigarettes per person 2.1M people affected
Stagnant pollution mixture over 3 metros, 1 day, peaking at 43.6 µg/m³ near Winston.
Reviewed source 1
Origin: Alaska
36.2 µg/m³ peak ≈ 1.1 cigarettes per person 6.6M people affected 2 top-ten days
Mixed causes over 5 metros, 1 day, peaking at 36.2 µg/m³ near Tampa. Origin traced to Alaska.
EPA AQS 4Agency/press 1
Origin: Alaska
56.4 µg/m³ peak ≈ 1.9 cigarettes per person 34M people affected
Wildfire smoke over 10 metros, 4 days, peaking at 56.4 µg/m³ near New York. Origin traced to Alaska.
EPA AQS 4Agency/press 3
93.4 µg/m³ peak ≈ 2.9 cigarettes per person 18M people affected 1 top-ten day
Fireworks over 2 metros, 1 day, peaking at 93.4 µg/m³ near Riverside.
46.8 µg/m³ peak ≈ 1.8 cigarettes per person 926k people affected 1 top-ten day
Fireworks over Albuquerque, 1 day, peaking at 46.8 µg/m³ near Albuquerque.
71.5 µg/m³ peak ≈ 2.6 cigarettes per person 2.4M people affected
Temperature inversion over Pittsburgh, 1 day, peaking at 71.5 µg/m³ near Pittsburgh.
Reviewed source 3 1
46.2 µg/m³ peak ≈ 1.5 cigarettes per person 7.8M people affected
Dust over Houston, 1 day, peaking at 46.2 µg/m³ near Houston.
71.3 µg/m³ peak ≈ 2.6 cigarettes per person 2.4M people affected
Other over Pittsburgh, 1 day, peaking at 71.3 µg/m³ near Pittsburgh.
state-local-official-archive-discovery-v2 1
44.2 µg/m³ peak ≈ 1.5 cigarettes per person 2.7M people affected
Regional secondary PM over 2 metros, 1 day, peaking at 44.2 µg/m³ near Bridgeport.
Reviewed source 1
93.8 µg/m³ peak ≈ 3.2 cigarettes per person 5.6M people affected 1 top-ten day
Temperature inversion over 2 metros, 1 day, peaking at 93.8 µg/m³ near Riverside.
Reviewed source 2
52 µg/m³ peak ≈ 2.0 cigarettes per person 1.0M people affected 1 top-ten day
Temperature inversion over Omaha, 1 day, peaking at 52 µg/m³ near Omaha.
Reviewed source 3
94.2 µg/m³ peak ≈ 5.1 cigarettes per person 2.7M people affected 1 city record set, 2 top-ten days
Temperature inversion over 3 metros, 2 days, peaking at 94.2 µg/m³ near Salt Lake City. 1 metro set an all-time record.
82 µg/m³ peak ≈ 3.3 cigarettes per person 2.1M people affected 1 top-ten day
Temperature inversion over 2 metros, 1 day, peaking at 82 µg/m³ near Provo.
77.5 µg/m³ peak ≈ 3.1 cigarettes per person 1.4M people affected 1 top-ten day
Temperature inversion over 2 metros, 2 days, peaking at 77.5 µg/m³ near Provo.
82.1 µg/m³ peak ≈ 4.6 cigarettes per person 1.4M people affected 1 top-ten day
Winter inversion over 2 metros, 2 days, peaking at 82.1 µg/m³ near Provo.
67.3 µg/m³ peak ≈ 2.5 cigarettes per person 3.3M people affected
Fireworks over San Diego, 1 day, peaking at 67.3 µg/m³ near San Diego.
43 µg/m³ peak ≈ 1.5 cigarettes per person 870k people affected 1 top-ten day
Fireworks over Columbia, 1 day, peaking at 43 µg/m³ near Columbia.
41.8 µg/m³ peak ≈ 1.5 cigarettes per person 966k people affected 1 top-ten day
Fireworks over New Orleans, 1 day, peaking at 41.8 µg/m³ near New Orleans.
91.8 µg/m³ peak ≈ 4.0 cigarettes per person 999k people affected 1 top-ten day
Other over Urban Honolulu, 1 day, peaking at 91.8 µg/m³ near Urban Honolulu.
239.2 µg/m³ peak ≈ 11.0 cigarettes per person 24M people affected 2 city records set, 4 top-ten days
Wildfire smoke over 5 metros, 4 days, peaking at 239.2 µg/m³ near San Diego. 2 metros set an all-time record.
EPA AQS 3Agency/press 2
58.1 µg/m³ peak ≈ 2.1 cigarettes per person 20M people affected
Temperature inversion over New York, 1 day, peaking at 58.1 µg/m³ near New York.
Reviewed source 2
86.9 µg/m³ peak ≈ 3.2 cigarettes per person 4.7M people affected
Stagnant pollution mixture over Riverside, 1 day, peaking at 86.9 µg/m³ near Riverside.
Reviewed source 5
51.1 µg/m³ peak ≈ 1.7 cigarettes per person 2.8M people affected
Stagnant pollution mixture over St. Louis, 1 day, peaking at 51.1 µg/m³ near St. Louis.
Reviewed source 1
45.9 µg/m³ peak ≈ 1.6 cigarettes per person 705k people affected
Regional secondary PM over Winston, 1 day, peaking at 45.9 µg/m³ near Winston.
Reviewed source 3
50 µg/m³ peak ≈ 1.8 cigarettes per person 958k people affected
Stagnant pollution mixture over Knoxville, 1 day, peaking at 50 µg/m³ near Knoxville.
47.7 µg/m³ peak ≈ 1.5 cigarettes per person 8.2M people affected
Regional secondary PM over 4 metros, 1 day, peaking at 47.7 µg/m³ near Bridgeport.
48.4 µg/m³ peak ≈ 1.7 cigarettes per person 6.1M people affected
Regional secondary PM over 4 metros, 2 days, peaking at 48.4 µg/m³ near Akron.
Reviewed source 1
44.5 µg/m³ peak ≈ 1.5 cigarettes per person 637k people affected
Regional secondary PM over Augusta, 1 day, peaking at 44.5 µg/m³ near Augusta.
Reviewed source 1
43.5 µg/m³ peak ≈ 1.6 cigarettes per person 1.4M people affected
Regional secondary PM over Richmond, 1 day, peaking at 43.5 µg/m³ near Richmond.
Reviewed source 1
60.3 µg/m³ peak ≈ 2.1 cigarettes per person 3.0M people affected 1 top-ten day
Regional secondary PM over 2 metros, 1 day, peaking at 60.3 µg/m³ near Columbus.
Reviewed source 1
39.4 µg/m³ peak ≈ 1.4 cigarettes per person 754k people affected
Stagnant pollution mixture over Des Moines, 1 day, peaking at 39.4 µg/m³ near Des Moines.
42.4 µg/m³ peak ≈ 1.4 cigarettes per person 2.2M people affected
Regional secondary PM over Nashville, 1 day, peaking at 42.4 µg/m³ near Nashville.
Reviewed source 1
121.2 µg/m³ peak ≈ 4.8 cigarettes per person 13M people affected 1 top-ten day
Fireworks over Los Angeles, 1 day, peaking at 121.2 µg/m³ near Los Angeles.
43.3 µg/m³ peak ≈ 1.6 cigarettes per person 881k people affected 1 top-ten day
Fireworks over Worcester, 1 day, peaking at 43.3 µg/m³ near Worcester.
84.6 µg/m³ peak ≈ 3.4 cigarettes per person 2.4M people affected 1 top-ten day
Fireworks over Las Vegas, 1 day, peaking at 84.6 µg/m³ near Las Vegas.
69.6 µg/m³ peak ≈ 1.9 cigarettes per person 3.3M people affected 1 top-ten day
Fireworks over 4 metros, 2 days, peaking at 69.6 µg/m³ near Scranton.
Reviewed source 2
63.4 µg/m³ peak ≈ 2.4 cigarettes per person 6.4M people affected 1 top-ten day
Prescribed fire over Washington, 1 day, peaking at 63.4 µg/m³ near Washington.
55.7 µg/m³ peak ≈ 2.0 cigarettes per person 1.4M people affected 1 top-ten day
Fireworks over Louisville/Jefferson County, 1 day, peaking at 55.7 µg/m³ near Louisville/Jefferson County.
Reviewed source 3
54.2 µg/m³ peak ≈ 2.0 cigarettes per person 6.4M people affected
Regional secondary PM over Washington, 1 day, peaking at 54.2 µg/m³ near Washington.
39.3 µg/m³ peak ≈ 1.3 cigarettes per person 588k people affected
Wildfire smoke over Chattanooga, 1 day, peaking at 39.3 µg/m³ near Chattanooga.
40.8 µg/m³ peak ≈ 1.5 cigarettes per person 881k people affected
Stagnant pollution mixture over Worcester, 1 day, peaking at 40.8 µg/m³ near Worcester.
Reviewed source 1
73.1 µg/m³ peak ≈ 2.5 cigarettes per person 16M people affected 4 top-ten days
Wildfire smoke over 4 metros, 1 day, peaking at 73.1 µg/m³ near Philadelphia.
Reviewed source 2Agency/press 1
69.3 µg/m³ peak ≈ 2.7 cigarettes per person 886k people affected
Mixed causes over Allentown, 1 day, peaking at 69.3 µg/m³ near Allentown.
Reviewed source 4
62.1 µg/m³ peak ≈ 3.1 cigarettes per person 5.3M people affected 3 top-ten days
Wildfire smoke over 4 metros, 2 days, peaking at 62.1 µg/m³ near Virginia Beach.
Reviewed source 2Agency/press 1
61.9 µg/m³ peak ≈ 2.4 cigarettes per person 574k people affected 1 top-ten day
Mixed causes over Scranton, 1 day, peaking at 61.9 µg/m³ near Scranton.
Reviewed source 3
60.2 µg/m³ peak ≈ 4.0 cigarettes per person 1.7M people affected 1 top-ten day
Stagnant pollution mixture over Providence, 2 days, peaking at 60.2 µg/m³ near Providence.
Reviewed source 1
58.9 µg/m³ peak ≈ 3.7 cigarettes per person 25M people affected 1 top-ten day
Mixed causes over 7 metros, 2 days, peaking at 58.9 µg/m³ near New York.
Reviewed source 2
50.7 µg/m³ peak ≈ 3.5 cigarettes per person 5.0M people affected
Stagnant pollution mixture over Boston, 2 days, peaking at 50.7 µg/m³ near Boston.
Reviewed source 1
46.9 µg/m³ peak ≈ 2.9 cigarettes per person 6.0M people affected
Wildfire smoke over 5 metros, 3 days, peaking at 46.9 µg/m³ near Chattanooga.
EPA AQS 4
85.2 µg/m³ peak ≈ 8.9 cigarettes per person 2.4M people affected 1 top-ten day
Stagnant pollution mixture over Pittsburgh, 3 days, peaking at 85.2 µg/m³ near Pittsburgh.
Reviewed source 2
49 µg/m³ peak ≈ 2.1 cigarettes per person 3.7M people affected
Mixed causes over 3 metros, 2 days, peaking at 49 µg/m³ near Akron.
Reviewed source 6
24.7 µg/m³ peak ≈ 0.8 cigarettes per person 658k people affected
Prescribed fire over Palm Bay, 1 day, peaking at 24.7 µg/m³ near Palm Bay.
Reviewed source 2
56.7 µg/m³ peak ≈ 3.3 cigarettes per person 17M people affected 2 top-ten days
Prescribed fire over 3 metros, 4 days, peaking at 56.7 µg/m³ near Dallas.
Reviewed source 3
Origin: Central American agricultural and biomass fires
45.7 µg/m³ peak ≈ 1.5 cigarettes per person 2.6M people affected 1 top-ten day
Wildfire smoke over 2 metros, 1 day, peaking at 45.7 µg/m³ near Oklahoma City. Origin traced to Central American agricultural and biomass fires.
Reviewed source 2
53.3 µg/m³ peak ≈ 2.0 cigarettes per person 915k people affected 1 top-ten day
Prescribed fire over McAllen, 1 day, peaking at 53.3 µg/m³ near McAllen.
62.5 µg/m³ peak ≈ 2.4 cigarettes per person 879k people affected
Dust over El Paso, 1 day, peaking at 62.5 µg/m³ near El Paso.
Reviewed source 3
59.5 µg/m³ peak ≈ 2.2 cigarettes per person 4.4M people affected
Temperature inversion over Detroit, 1 day, peaking at 59.5 µg/m³ near Detroit.
71.4 µg/m³ peak ≈ 2.8 cigarettes per person 2.3M people affected 1 city record set
Regional secondary PM over Kansas City, 1 day, peaking at 71.4 µg/m³ near Kansas City. 1 metro set an all-time record.
56.7 µg/m³ peak ≈ 2.1 cigarettes per person 615k people affected
Regional secondary PM over Harrisburg, 1 day, peaking at 56.7 µg/m³ near Harrisburg.
Reviewed source 3
57.9 µg/m³ peak ≈ 2.1 cigarettes per person 2.2M people affected
Temperature inversion over Cleveland, 1 day, peaking at 57.9 µg/m³ near Cleveland.
57.8 µg/m³ peak ≈ 2.0 cigarettes per person 2.2M people affected
Regional secondary PM over Indianapolis, 1 day, peaking at 57.8 µg/m³ near Indianapolis.
Reviewed source 3
70.3 µg/m³ peak ≈ 4.6 cigarettes per person 4.4M people affected
Temperature inversion over Detroit, 2 days, peaking at 70.3 µg/m³ near Detroit.
47.6 µg/m³ peak ≈ 1.8 cigarettes per person 577k people affected
Temperature inversion over New Haven, 1 day, peaking at 47.6 µg/m³ near New Haven.
Reviewed source 3
51.1 µg/m³ peak ≈ 2.0 cigarettes per person 464k people affected
Regional secondary PM over Springfield, 1 day, peaking at 51.1 µg/m³ near Springfield.
50.4 µg/m³ peak ≈ 2.0 cigarettes per person 913k people affected 1 top-ten day
Temperature inversion over Albany, 1 day, peaking at 50.4 µg/m³ near Albany.
Reviewed source 3
47.6 µg/m³ peak ≈ 1.8 cigarettes per person 464k people affected
Temperature inversion over Springfield, 1 day, peaking at 47.6 µg/m³ near Springfield.
Reviewed source 3
126.1 µg/m³ peak ≈ 6.5 cigarettes per person 2.8M people affected 1 city record set
Fireworks over San Antonio, 2 days, peaking at 126.1 µg/m³ near San Antonio. 1 metro set an all-time record.
57 µg/m³ peak ≈ 4.3 cigarettes per person 999k people affected 1 top-ten day
Other over Urban Honolulu, 2 days, peaking at 57 µg/m³ near Urban Honolulu.
EPA AQS 2
53.5 µg/m³ peak ≈ 2.0 cigarettes per person 1.2M people affected
Temperature inversion over Grand Rapids, 1 day, peaking at 53.5 µg/m³ near Grand Rapids.
65.8 µg/m³ peak ≈ 2.4 cigarettes per person 4.4M people affected
Stagnant pollution mixture over Detroit, 1 day, peaking at 65.8 µg/m³ near Detroit.
Reviewed source 3
62.7 µg/m³ peak ≈ 2.6 cigarettes per person 6.0M people affected 3 top-ten days
Other over 4 metros, 2 days, peaking at 62.7 µg/m³ near Raleigh.
EPA AQS 4
72.4 µg/m³ peak ≈ 3.0 cigarettes per person 846k people affected 1 top-ten day
Temperature inversion over Boise City, 1 day, peaking at 72.4 µg/m³ near Boise City.
Reviewed source 1
66 µg/m³ peak ≈ 2.7 cigarettes per person 2.5M people affected
Temperature inversion over Portland, 1 day, peaking at 66 µg/m³ near Portland.
Reviewed source 1
61.7 µg/m³ peak ≈ 2.5 cigarettes per person 846k people affected 1 top-ten day
Temperature inversion over Boise City, 1 day, peaking at 61.7 µg/m³ near Boise City.
Reviewed source 1
91 µg/m³ peak ≈ 3.7 cigarettes per person 2.5M people affected
Stagnant pollution mixture over Sacramento, 1 day, peaking at 91 µg/m³ near Sacramento.
Reviewed source 2
76.7 µg/m³ peak ≈ 3.0 cigarettes per person 4.6M people affected
Stagnant pollution mixture over San Francisco, 1 day, peaking at 76.7 µg/m³ near San Francisco.
82.1 µg/m³ peak ≈ 3.0 cigarettes per person 4.7M people affected
Stagnant pollution mixture over Riverside, 1 day, peaking at 82.1 µg/m³ near Riverside.
Reviewed source 3
39.7 µg/m³ peak ≈ 1.3 cigarettes per person 1.8M people affected
Regional secondary PM over 2 metros, 1 day, peaking at 39.7 µg/m³ near New Orleans.
Reviewed source 1
57.5 µg/m³ peak ≈ 5.9 cigarettes per person 21M people affected 4 top-ten days
Industrial over 4 metros, 4 days, peaking at 57.5 µg/m³ near Houston.
Agency/press 2
48.2 µg/m³ peak ≈ 2.3 cigarettes per person 1.5M people affected 1 top-ten day
Stagnant pollution mixture over 2 metros, 2 days, peaking at 48.2 µg/m³ near Jackson.
47.3 µg/m³ peak ≈ 1.6 cigarettes per person 2.1M people affected 1 top-ten day
Regional secondary PM over 2 metros, 1 day, peaking at 47.3 µg/m³ near Memphis.
Reviewed source 1
69.6 µg/m³ peak ≈ 2.6 cigarettes per person 22M people affected 4 top-ten days
Regional secondary PM over 14 metros, 5 days, peaking at 69.6 µg/m³ near Pittsburgh.
Agency/press 1Reviewed source 2
40 µg/m³ peak ≈ 1.6 cigarettes per person 655k people affected
Regional secondary PM over Syracuse, 1 day, peaking at 40 µg/m³ near Syracuse.
58.9 µg/m³ peak ≈ 2.7 cigarettes per person 16M people affected
Regional secondary PM over 4 metros, 2 days, peaking at 58.9 µg/m³ near Philadelphia.
49.4 µg/m³ peak ≈ 1.9 cigarettes per person 1.8M people affected
Regional secondary PM over Virginia Beach, 1 day, peaking at 49.4 µg/m³ near Virginia Beach.
Reviewed source 2
46.2 µg/m³ peak ≈ 1.7 cigarettes per person 1.4M people affected
Stagnant pollution mixture over Richmond, 1 day, peaking at 46.2 µg/m³ near Richmond.
49.8 µg/m³ peak ≈ 2.4 cigarettes per person 5.6M people affected 3 top-ten days
Wildfire smoke over 4 metros, 2 days, peaking at 49.8 µg/m³ near Greenville.
EPA AQS 6
47.5 µg/m³ peak ≈ 2.4 cigarettes per person 1.4M people affected 1 top-ten day
Stagnant pollution mixture over 2 metros, 2 days, peaking at 47.5 µg/m³ near Durham.
Reviewed source 7
80.2 µg/m³ peak ≈ 7.2 cigarettes per person 1.4M people affected 1 top-ten day
Stagnant pollution mixture over Louisville/Jefferson County, 3 days, peaking at 80.2 µg/m³ near Louisville/Jefferson County.
Reviewed source 3
27.6 µg/m³ peak ≈ 1.0 cigarettes per person 1.1M people affected
Dust over Tucson, 1 day, peaking at 27.6 µg/m³ near Tucson.
43 µg/m³ peak ≈ 2.7 cigarettes per person 8.3M people affected
Temperature inversion over Dallas, 2 days, peaking at 43 µg/m³ near Dallas.
Reviewed source 4
Origin: Quebec
118.4 µg/m³ peak ≈ 6.7 cigarettes per person 44M people affected 2 city records set, 15 top-ten days
Wildfire smoke over 15 metros, 4 days, peaking at 118.4 µg/m³ near Philadelphia. 2 metros set an all-time record. Origin traced to Quebec.
EPA AQS 34Agency/press 4
40.7 µg/m³ peak ≈ 2.7 cigarettes per person 2.3M people affected
Regional secondary PM over Kansas City, 2 days, peaking at 40.7 µg/m³ near Kansas City.
34.5 µg/m³ peak ≈ 1.2 cigarettes per person 3.4M people affected
Fireworks over Tampa, 1 day, peaking at 34.5 µg/m³ near Tampa.
100.6 µg/m³ peak ≈ 3.1 cigarettes per person 5.9M people affected 1 city record set, 2 top-ten days
Fireworks over 3 metros, 2 days, peaking at 100.6 µg/m³ near Louisville/Jefferson County. 1 metro set an all-time record.
88.8 µg/m³ peak ≈ 5.9 cigarettes per person 2.8M people affected 1 city record set
Fireworks over St. Louis, 2 days, peaking at 88.8 µg/m³ near St. Louis. 1 metro set an all-time record.
66.8 µg/m³ peak ≈ 2.3 cigarettes per person 8.0M people affected 2 top-ten days
Fireworks over 3 metros, 1 day, peaking at 66.8 µg/m³ near Miami.
61.7 µg/m³ peak ≈ 2.3 cigarettes per person 6.4M people affected
Fireworks over Washington, 1 day, peaking at 61.7 µg/m³ near Washington.
Reviewed source 1
41 µg/m³ peak ≈ 1.4 cigarettes per person 870k people affected
Fireworks over Columbia, 1 day, peaking at 41 µg/m³ near Columbia.
37.2 µg/m³ peak ≈ 1.2 cigarettes per person 1.1M people affected
Fireworks over Tulsa, 1 day, peaking at 37.2 µg/m³ near Tulsa.
57.8 µg/m³ peak ≈ 2.0 cigarettes per person 6.3M people affected
Stagnant pollution mixture over Philadelphia, 1 day, peaking at 57.8 µg/m³ near Philadelphia.
Reviewed source 1
55.5 µg/m³ peak ≈ 4.2 cigarettes per person 9.3M people affected
Stagnant pollution mixture over 2 metros, 2 days, peaking at 55.5 µg/m³ near Washington.
50.5 µg/m³ peak ≈ 3.4 cigarettes per person 1.4M people affected 1 top-ten day
Regional secondary PM over Richmond, 3 days, peaking at 50.5 µg/m³ near Richmond.
78.4 µg/m³ peak ≈ 2.4 cigarettes per person 6.9M people affected 1 city record set, 3 top-ten days
Regional secondary PM over 4 metros, 2 days, peaking at 78.4 µg/m³ near Springfield. 1 metro set an all-time record.
Reviewed source 2
53.4 µg/m³ peak ≈ 2.2 cigarettes per person 2.3M people affected 1 top-ten day
Regional secondary PM over 3 metros, 2 days, peaking at 53.4 µg/m³ near Scranton.
50.4 µg/m³ peak ≈ 1.9 cigarettes per person 1.2M people affected 1 top-ten day
Stagnant pollution mixture over Buffalo, 1 day, peaking at 50.4 µg/m³ near Buffalo.
50.6 µg/m³ peak ≈ 1.7 cigarettes per person 2.3M people affected
Stagnant pollution mixture over Cincinnati, 1 day, peaking at 50.6 µg/m³ near Cincinnati.
Reviewed source 4
59.6 µg/m³ peak ≈ 2.2 cigarettes per person 9.3M people affected 1 top-ten day
Regional secondary PM over 2 metros, 1 day, peaking at 59.6 µg/m³ near Baltimore.
46.8 µg/m³ peak ≈ 1.8 cigarettes per person 1.2M people affected
Stagnant pollution mixture over Buffalo, 1 day, peaking at 46.8 µg/m³ near Buffalo.
Reviewed source 3
60.6 µg/m³ peak ≈ 2.2 cigarettes per person 4.4M people affected
Mixed causes over Detroit, 1 day, peaking at 60.6 µg/m³ near Detroit.
Reviewed source 1
51.3 µg/m³ peak ≈ 1.7 cigarettes per person 2.9M people affected
Stagnant pollution mixture over 2 metros, 2 days, peaking at 51.3 µg/m³ near Akron.
Reviewed source 2
48 µg/m³ peak ≈ 1.6 cigarettes per person 2.3M people affected
Stagnant pollution mixture over Cincinnati, 1 day, peaking at 48 µg/m³ near Cincinnati.
37.4 µg/m³ peak ≈ 1.3 cigarettes per person 870k people affected
Wildfire smoke over Columbia, 1 day, peaking at 37.4 µg/m³ near Columbia.
47.4 µg/m³ peak ≈ 1.8 cigarettes per person 870k people affected 1 top-ten day
Wildfire smoke over Charleston, 1 day, peaking at 47.4 µg/m³ near Charleston.
Reviewed source 2
100.2 µg/m³ peak ≈ 6.2 cigarettes per person 2.0M people affected 1 city record set, 2 top-ten days
Winter inversion over 2 metros, 2 days, peaking at 100.2 µg/m³ near Ogden. 1 metro set an all-time record.
Agency/press 1 1
59.8 µg/m³ peak ≈ 2.4 cigarettes per person 668k people affected
Temperature inversion over Ogden, 1 day, peaking at 59.8 µg/m³ near Ogden.
25.6 µg/m³ peak ≈ 0.9 cigarettes per person 935k people affected
Temperature inversion over North Port, 1 day, peaking at 25.6 µg/m³ near North Port.
Reviewed source 3
24.4 µg/m³ peak ≈ 0.8 cigarettes per person 853k people affected
Prescribed fire over Lakeland, 1 day, peaking at 24.4 µg/m³ near Lakeland.
Reviewed source 2
58.3 µg/m³ peak ≈ 2.3 cigarettes per person 668k people affected
Stagnant pollution mixture over Ogden, 1 day, peaking at 58.3 µg/m³ near Ogden.
Reviewed source 3
87.3 µg/m³ peak ≈ 6.0 cigarettes per person 999k people affected 1 top-ten day
Other over Urban Honolulu, 2 days, peaking at 87.3 µg/m³ near Urban Honolulu.
EPA AQS 2Agency/press 2
83 µg/m³ peak ≈ 9.1 cigarettes per person 2.7M people affected 3 top-ten days
Temperature inversion over 3 metros, 5 days, peaking at 83 µg/m³ near Provo.
Reviewed source 3Agency/press 1
71.6 µg/m³ peak ≈ 2.7 cigarettes per person 2.2M people affected 1 top-ten day
Stagnant pollution mixture over Cleveland, 1 day, peaking at 71.6 µg/m³ near Cleveland.
Reviewed source 4
40.1 µg/m³ peak ≈ 1.3 cigarettes per person 7.8M people affected
Stagnant pollution mixture over Houston, 1 day, peaking at 40.1 µg/m³ near Houston.
Reviewed source 3
53.4 µg/m³ peak ≈ 1.8 cigarettes per person 2.3M people affected 1 top-ten day
Temperature inversion over Cincinnati, 1 day, peaking at 53.4 µg/m³ near Cincinnati.
Reviewed source 3
78.1 µg/m³ peak ≈ 3.1 cigarettes per person 9.0M people affected 2 top-ten days
Wildfire smoke over 4 metros, 6 days, peaking at 78.1 µg/m³ near Knoxville.
EPA AQS 9
54.2 µg/m³ peak ≈ 1.9 cigarettes per person 1.2M people affected
Mixed causes over Birmingham, 1 day, peaking at 54.2 µg/m³ near Birmingham.
Reviewed source 3
85.5 µg/m³ peak ≈ 3.1 cigarettes per person 4.7M people affected
Temperature inversion over Riverside, 1 day, peaking at 85.5 µg/m³ near Riverside.
94.7 µg/m³ peak ≈ 3.6 cigarettes per person 13M people affected 1 top-ten day
Temperature inversion over Los Angeles, 1 day, peaking at 94.7 µg/m³ near Los Angeles.
98 µg/m³ peak ≈ 3.6 cigarettes per person 5.6M people affected 2 top-ten days
Temperature inversion over 2 metros, 2 days, peaking at 98 µg/m³ near Riverside.
Reviewed source 2
58.9 µg/m³ peak ≈ 2.1 cigarettes per person 1.2M people affected
Wildfire smoke over Birmingham, 1 day, peaking at 58.9 µg/m³ near Birmingham.
Reviewed source 2
54.6 µg/m³ peak ≈ 1.9 cigarettes per person 20M people affected
Other over New York, 1 day, peaking at 54.6 µg/m³ near New York.
59 µg/m³ peak ≈ 2.1 cigarettes per person 6.3M people affected
Regional secondary PM over Philadelphia, 1 day, peaking at 59 µg/m³ near Philadelphia.
Reviewed source 1
61.7 µg/m³ peak ≈ 2.3 cigarettes per person 958k people affected 1 top-ten day
Regional secondary PM over Knoxville, 1 day, peaking at 61.7 µg/m³ near Knoxville.
Reviewed source 2
40.5 µg/m³ peak ≈ 1.3 cigarettes per person 2.9M people affected
Stagnant pollution mixture over Charlotte, 1 day, peaking at 40.5 µg/m³ near Charlotte.
Origin: Eastern Seaboard, United States
53.4 µg/m³ peak ≈ 2.1 cigarettes per person 11M people affected
Other over 3 metros, 2 days, peaking at 53.4 µg/m³ near Baltimore. Origin traced to Eastern Seaboard, United States.
Agency/press 1
51.5 µg/m³ peak ≈ 3.3 cigarettes per person 5.1M people affected 5 top-ten days
Stagnant pollution mixture over 5 metros, 3 days, peaking at 51.5 µg/m³ near Richmond.
Reviewed source 1
56.8 µg/m³ peak ≈ 2.0 cigarettes per person 2.2M people affected
Temperature inversion over Indianapolis, 3 days, peaking at 56.8 µg/m³ near Indianapolis.
53.2 µg/m³ peak ≈ 4.2 cigarettes per person 3.1M people affected
Stagnant pollution mixture over 2 metros, 3 days, peaking at 53.2 µg/m³ near Cincinnati.
Reviewed source 5
46.4 µg/m³ peak ≈ 1.6 cigarettes per person 2.2M people affected
Stagnant pollution mixture over Columbus, 3 days, peaking at 46.4 µg/m³ near Columbus.
Reviewed source 3
51.3 µg/m³ peak ≈ 1.8 cigarettes per person 2.9M people affected
Stagnant pollution mixture over Baltimore, 1 day, peaking at 51.3 µg/m³ near Baltimore.
Reviewed source 1
60.8 µg/m³ peak ≈ 2.2 cigarettes per person 1.4M people affected 1 top-ten day
Regional secondary PM over Louisville/Jefferson County, 1 day, peaking at 60.8 µg/m³ near Louisville/Jefferson County.
Reviewed source 3
57.7 µg/m³ peak ≈ 2.4 cigarettes per person 8.1M people affected 4 top-ten days
Regional secondary PM over 6 metros, 2 days, peaking at 57.7 µg/m³ near Akron.
Reviewed source 8
47.9 µg/m³ peak ≈ 1.6 cigarettes per person 1.4M people affected
Regional secondary PM over Louisville/Jefferson County, 1 day, peaking at 47.9 µg/m³ near Louisville/Jefferson County.
37.5 µg/m³ peak ≈ 1.4 cigarettes per person 655k people affected
Regional secondary PM over Syracuse, 1 day, peaking at 37.5 µg/m³ near Syracuse.
45.4 µg/m³ peak ≈ 1.6 cigarettes per person 822k people affected
Stagnant pollution mixture over Dayton, 1 day, peaking at 45.4 µg/m³ near Dayton.
60.2 µg/m³ peak ≈ 2.3 cigarettes per person 2.2M people affected 1 top-ten day
Stagnant pollution mixture over Columbus, 1 day, peaking at 60.2 µg/m³ near Columbus.
57.3 µg/m³ peak ≈ 2.1 cigarettes per person 4.4M people affected
Stagnant pollution mixture over Detroit, 1 day, peaking at 57.3 µg/m³ near Detroit.
47.7 µg/m³ peak ≈ 1.7 cigarettes per person 1.2M people affected
Stagnant pollution mixture over Grand Rapids, 1 day, peaking at 47.7 µg/m³ near Grand Rapids.
Reviewed source 1
57.4 µg/m³ peak ≈ 3.7 cigarettes per person 702k people affected 1 top-ten day
Regional secondary PM over Akron, 2 days, peaking at 57.4 µg/m³ near Akron.
Reviewed source 5
44.7 µg/m³ peak ≈ 1.5 cigarettes per person 4.4M people affected
Stagnant pollution mixture over 3 metros, 1 day, peaking at 44.7 µg/m³ near Charlotte.
Reviewed source 3
41 µg/m³ peak ≈ 1.4 cigarettes per person 588k people affected
Regional secondary PM over Chattanooga, 1 day, peaking at 41 µg/m³ near Chattanooga.
Reviewed source 3
39.1 µg/m³ peak ≈ 1.4 cigarettes per person 1.4M people affected
Regional secondary PM over Richmond, 1 day, peaking at 39.1 µg/m³ near Richmond.
86.5 µg/m³ peak ≈ 3.4 cigarettes per person 958k people affected 1 top-ten day
Regional secondary PM over Knoxville, 1 day, peaking at 86.5 µg/m³ near Knoxville.
Reviewed source 1
77.4 µg/m³ peak ≈ 2.9 cigarettes per person 6.4M people affected 1 top-ten day
Regional secondary PM over Atlanta, 1 day, peaking at 77.4 µg/m³ near Atlanta.
Reviewed source 1
61.7 µg/m³ peak ≈ 2.2 cigarettes per person 6.4M people affected
Regional secondary PM over Atlanta, 1 day, peaking at 61.7 µg/m³ near Atlanta.
Reviewed source 1
54.2 µg/m³ peak ≈ 2.1 cigarettes per person 6.5M people affected 1 top-ten day
Fireworks over Miami, 1 day, peaking at 54.2 µg/m³ near Miami.
57.3 µg/m³ peak ≈ 2.0 cigarettes per person 9.4M people affected
Fireworks over Chicago, 1 day, peaking at 57.3 µg/m³ near Chicago.
50 µg/m³ peak ≈ 1.8 cigarettes per person 835k people affected 1 top-ten day
Fireworks over Oxnard, 1 day, peaking at 50 µg/m³ near Oxnard.
39.4 µg/m³ peak ≈ 1.3 cigarettes per person 2.3M people affected
Fireworks over Kansas City, 1 day, peaking at 39.4 µg/m³ near Kansas City.
43.4 µg/m³ peak ≈ 1.6 cigarettes per person 1.7M people affected
Regional secondary PM over Providence, 1 day, peaking at 43.4 µg/m³ near Providence.
39.9 µg/m³ peak ≈ 1.5 cigarettes per person 1.7M people affected
Mixed causes over 2 metros, 1 day, peaking at 39.9 µg/m³ near Rochester.
62.1 µg/m³ peak ≈ 2.0 cigarettes per person 23M people affected 1 top-ten day
Mixed causes over 3 metros, 2 days, peaking at 62.1 µg/m³ near Baltimore.
Agency/press 1Reviewed source 1
50.5 µg/m³ peak ≈ 1.8 cigarettes per person 8.2M people affected
Mixed causes over 2 metros, 1 day, peaking at 50.5 µg/m³ near Washington.
Agency/press 1Reviewed source 1
47.5 µg/m³ peak ≈ 1.6 cigarettes per person 1.9M people affected
Mixed causes over 2 metros, 2 days, peaking at 47.5 µg/m³ near Akron.
42.3 µg/m³ peak ≈ 1.4 cigarettes per person 1.5M people affected
Stagnant pollution mixture over 2 metros, 1 day, peaking at 42.3 µg/m³ near Winston.
Reviewed source 1
42 µg/m³ peak ≈ 1.6 cigarettes per person 913k people affected
Regional secondary PM over Albany, 1 day, peaking at 42 µg/m³ near Albany.
Reviewed source 1
49.9 µg/m³ peak ≈ 1.7 cigarettes per person 1.4M people affected
Regional secondary PM over Louisville/Jefferson County, 1 day, peaking at 49.9 µg/m³ near Louisville/Jefferson County.
31.7 µg/m³ peak ≈ 1.1 cigarettes per person 740k people affected 1 top-ten day
Wildfire smoke over Deltona, 1 day, peaking at 31.7 µg/m³ near Deltona.
Reviewed source 2
73.9 µg/m³ peak ≈ 2.8 cigarettes per person 958k people affected 1 top-ten day
Stagnant pollution mixture over Knoxville, 1 day, peaking at 73.9 µg/m³ near Knoxville.
Reviewed source 4
Named source 800-acre fire near Orlando · Orlando area, Florida
60.5 µg/m³ peak ≈ 3.8 cigarettes per person 4.7M people affected 2 top-ten days
Wildfire smoke over 2 metros, 3 days, peaking at 60.5 µg/m³ near Orlando. Origin traced to Orlando area, Florida.
EPA AQS 6Agency/press 1
87.9 µg/m³ peak ≈ 3.2 cigarettes per person 4.7M people affected
Temperature inversion over Riverside, 1 day, peaking at 87.9 µg/m³ near Riverside.
Reviewed source 2
33.8 µg/m³ peak ≈ 1.1 cigarettes per person 3.8M people affected
Wildfire smoke over 2 metros, 2 days, peaking at 33.8 µg/m³ near Orlando.
Reviewed source 1Agency/press 1
55.1 µg/m³ peak ≈ 1.6 cigarettes per person 6.0M people affected
Dust over 2 metros, 1 day, peaking at 55.1 µg/m³ near Bridgeport.
Reviewed source 1
Origin: May 2001 Asian dust episode
98.6 µg/m³ peak ≈ 6.9 cigarettes per person 3.6M people affected 1 top-ten day
Dust over 2 metros, 3 days, peaking at 98.6 µg/m³ near Pittsburgh. Origin traced to May 2001 Asian dust episode.
Reviewed source 2
82.7 µg/m³ peak ≈ 3.0 cigarettes per person 4.7M people affected
Stagnant pollution mixture over Riverside, 1 day, peaking at 82.7 µg/m³ near Riverside.
Reviewed source 3
82.9 µg/m³ peak ≈ 3.3 cigarettes per person 879k people affected
Dust over El Paso, 1 day, peaking at 82.9 µg/m³ near El Paso.
25.9 µg/m³ peak ≈ 0.8 cigarettes per person 853k people affected
Wildfire smoke over Lakeland, 1 day, peaking at 25.9 µg/m³ near Lakeland.
Reviewed source 4
40.6 µg/m³ peak ≈ 1.5 cigarettes per person 2.9M people affected 1 top-ten day
Wildfire smoke over Orlando, 1 day, peaking at 40.6 µg/m³ near Orlando.
Reviewed source 3
Origin: Polk County, Florida
59.2 µg/m³ peak ≈ 1.7 cigarettes per person 4.7M people affected 3 top-ten days
Wildfire smoke over 3 metros, 2 days, peaking at 59.2 µg/m³ near Lakeland. Origin traced to Polk County, Florida.
Agency/press 3
68.4 µg/m³ peak ≈ 7.2 cigarettes per person 3.1M people affected 1 top-ten day
Temperature inversion over Denver, 3 days, peaking at 68.4 µg/m³ near Denver.
105.7 µg/m³ peak ≈ 8.3 cigarettes per person 923k people affected
Stagnant pollution mixture over Bakersfield, 2 days, peaking at 105.7 µg/m³ near Bakersfield.
Reviewed source 1 1
61.3 µg/m³ peak ≈ 2.5 cigarettes per person 846k people affected
Temperature inversion over Boise City, 1 day, peaking at 61.3 µg/m³ near Boise City.
Reviewed source 2
76.6 µg/m³ peak ≈ 3.2 cigarettes per person 846k people affected 1 top-ten day
Temperature inversion over Boise City, 1 day, peaking at 76.6 µg/m³ near Boise City.
35.4 µg/m³ peak ≈ 1.3 cigarettes per person 853k people affected 1 top-ten day
Wildfire smoke over Lakeland, 1 day, peaking at 35.4 µg/m³ near Lakeland.
Reviewed source 2
63.4 µg/m³ peak ≈ 2.5 cigarettes per person 464k people affected 1 top-ten day
Temperature inversion over Springfield, 1 day, peaking at 63.4 µg/m³ near Springfield.
90.2 µg/m³ peak ≈ 3.4 cigarettes per person 2.4M people affected 1 top-ten day
Temperature inversion over Pittsburgh, 1 day, peaking at 90.2 µg/m³ near Pittsburgh.
Reviewed source 2
73.5 µg/m³ peak ≈ 4.9 cigarettes per person 886k people affected 1 top-ten day
Stagnant pollution mixture over Allentown, 2 days, peaking at 73.5 µg/m³ near Allentown.
Reviewed source 3
59.6 µg/m³ peak ≈ 2.9 cigarettes per person 16M people affected
Temperature inversion over 3 metros, 2 days, peaking at 59.6 µg/m³ near Philadelphia.
55.3 µg/m³ peak ≈ 2.0 cigarettes per person 20M people affected
Temperature inversion over New York, 1 day, peaking at 55.3 µg/m³ near New York.
Reviewed source 3
41.1 µg/m³ peak ≈ 1.5 cigarettes per person 1.2M people affected
Temperature inversion over Hartford, 1 day, peaking at 41.1 µg/m³ near Hartford.
120.4 µg/m³ peak ≈ 4.9 cigarettes per person 923k people affected 1 top-ten day
Stagnant pollution mixture over Bakersfield, 1 day, peaking at 120.4 µg/m³ near Bakersfield.
Reviewed source 2
52.2 µg/m³ peak ≈ 1.8 cigarettes per person 2.8M people affected
Mixed causes over St. Louis, 1 day, peaking at 52.2 µg/m³ near St. Louis.
Reviewed source 2
85.6 µg/m³ peak ≈ 3.5 cigarettes per person 2.0M people affected 1 top-ten day
Residential combustion over San Jose, 1 day, peaking at 85.6 µg/m³ near San Jose.
Reviewed source 2
76.6 µg/m³ peak ≈ 3.0 cigarettes per person 4.6M people affected
Residential combustion over San Francisco, 1 day, peaking at 76.6 µg/m³ near San Francisco.
58.2 µg/m³ peak ≈ 2.2 cigarettes per person 577k people affected 1 top-ten day
Stagnant pollution mixture over New Haven, 1 day, peaking at 58.2 µg/m³ near New Haven.
Reviewed source 3
Origin: Maryland–Mid-Atlantic
70.5 µg/m³ peak ≈ 2.3 cigarettes per person 4.9M people affected
Winter inversion over 4 metros, 4 days, peaking at 70.5 µg/m³ near Allentown. Origin traced to Maryland–Mid-Atlantic.
61.3 µg/m³ peak ≈ 2.5 cigarettes per person 3.7M people affected 2 top-ten days
Stagnant pollution mixture over 3 metros, 2 days, peaking at 61.3 µg/m³ near Columbus.
Agency/press 1Reviewed source 1
107.5 µg/m³ peak ≈ 4.4 cigarettes per person 4.6M people affected
Mixed causes over San Francisco, 1 day, peaking at 107.5 µg/m³ near San Francisco.
Reviewed source 2
74 µg/m³ peak ≈ 3.0 cigarettes per person 761k people affected
Temperature inversion over Provo, 1 day, peaking at 74 µg/m³ near Provo.
58.3 µg/m³ peak ≈ 2.3 cigarettes per person 846k people affected
Temperature inversion over Boise City, 1 day, peaking at 58.3 µg/m³ near Boise City.
Reviewed source 3
Origin: San Joaquin Valley, California
154.7 µg/m³ peak ≈ 6.7 cigarettes per person 1.8M people affected 1 top-ten day
Other over 2 metros, 4 days, peaking at 154.7 µg/m³ near Bakersfield. Origin traced to San Joaquin Valley, California.
Agency/press 1
72.1 µg/m³ peak ≈ 2.9 cigarettes per person 1.3M people affected
Temperature inversion over Salt Lake City, 1 day, peaking at 72.1 µg/m³ near Salt Lake City.
63.3 µg/m³ peak ≈ 2.5 cigarettes per person 2.0M people affected
Stagnant pollution mixture over San Jose, 1 day, peaking at 63.3 µg/m³ near San Jose.
80 µg/m³ peak ≈ 3.2 cigarettes per person 2.0M people affected
Fireworks over San Jose, 1 day, peaking at 80 µg/m³ near San Jose.
Reviewed source 2
77.7 µg/m³ peak ≈ 3.1 cigarettes per person 4.6M people affected
Fireworks over San Francisco, 1 day, peaking at 77.7 µg/m³ near San Francisco.
Reviewed source 2
77.3 µg/m³ peak ≈ 2.7 cigarettes per person 16M people affected
Fireworks over 2 metros, 1 day, peaking at 77.3 µg/m³ near Los Angeles.
74.1 µg/m³ peak ≈ 2.9 cigarettes per person 879k people affected
Fireworks over El Paso, 1 day, peaking at 74.1 µg/m³ near El Paso.
63.4 µg/m³ peak ≈ 2.3 cigarettes per person 5.2M people affected
Fireworks over Phoenix, 1 day, peaking at 63.4 µg/m³ near Phoenix.
Reviewed source 1state-local-official-archive-discovery-v1 1 1
Origin: Oʻahu, Hawaii
130.1 µg/m³ peak ≈ 5.7 cigarettes per person 999k people affected 1 city record set
Fireworks over Urban Honolulu, 1 day, peaking at 130.1 µg/m³ near Urban Honolulu. 1 metro set an all-time record. Origin traced to Oʻahu, Hawaii.
EPA AQS 1Agency/press 2
47.1 µg/m³ peak ≈ 3.3 cigarettes per person 2.4M people affected
Fireworks over Las Vegas, 2 days, peaking at 47.1 µg/m³ near Las Vegas.
72.4 µg/m³ peak ≈ 2.9 cigarettes per person 1.3M people affected
Temperature inversion over Salt Lake City, 1 day, peaking at 72.4 µg/m³ near Salt Lake City.
Origin: California Central Valley
112.7 µg/m³ peak ≈ 8.2 cigarettes per person 2.9M people affected
Other over 2 metros, 3 days, peaking at 112.7 µg/m³ near Bakersfield. Origin traced to California Central Valley.
Agency/press 1
84.5 µg/m³ peak ≈ 3.1 cigarettes per person 4.7M people affected
Temperature inversion over Riverside, 1 day, peaking at 84.5 µg/m³ near Riverside.
65.9 µg/m³ peak ≈ 2.4 cigarettes per person 3.3M people affected
Temperature inversion over San Diego, 1 day, peaking at 65.9 µg/m³ near San Diego.
83 µg/m³ peak ≈ 6.0 cigarettes per person 13M people affected
Temperature inversion over Los Angeles, 2 days, peaking at 83 µg/m³ near Los Angeles.
43.5 µg/m³ peak ≈ 1.5 cigarettes per person 835k people affected
Temperature inversion over Oxnard, 1 day, peaking at 43.5 µg/m³ near Oxnard.
63.4 µg/m³ peak ≈ 2.5 cigarettes per person 2.0M people affected
Stagnant pollution mixture over San Jose, 1 day, peaking at 63.4 µg/m³ near San Jose.
80.6 µg/m³ peak ≈ 2.9 cigarettes per person 4.7M people affected
Stagnant pollution mixture over Riverside, 1 day, peaking at 80.6 µg/m³ near Riverside.
Reviewed source 5
66.3 µg/m³ peak ≈ 4.7 cigarettes per person 3.3M people affected
Temperature inversion over San Diego, 2 days, peaking at 66.3 µg/m³ near San Diego.
Reviewed source 4
113.9 µg/m³ peak ≈ 11.6 cigarettes per person 13M people affected 1 top-ten day
Stagnant pollution mixture over Los Angeles, 3 days, peaking at 113.9 µg/m³ near Los Angeles.
Reviewed source 1
87.5 µg/m³ peak ≈ 3.3 cigarettes per person 13M people affected
Stagnant pollution mixture over Los Angeles, 1 day, peaking at 87.5 µg/m³ near Los Angeles.
Reviewed source 1
52.7 µg/m³ peak ≈ 2.0 cigarettes per person 3.8M people affected
Temperature inversion over Minneapolis, 1 day, peaking at 52.7 µg/m³ near Minneapolis.
Reviewed source 4
107.1 µg/m³ peak ≈ 4.3 cigarettes per person 923k people affected
Stagnant pollution mixture over Bakersfield, 1 day, peaking at 107.1 µg/m³ near Bakersfield.
38.9 µg/m³ peak ≈ 1.3 cigarettes per person 1.4M people affected
Wildfire smoke over Richmond, 1 day, peaking at 38.9 µg/m³ near Richmond.
54.7 µg/m³ peak ≈ 1.9 cigarettes per person 7.1M people affected
Wildfire smoke over 2 metros, 2 days, peaking at 54.7 µg/m³ near Harrisburg.
40.3 µg/m³ peak ≈ 2.7 cigarettes per person 5.8M people affected
Temperature inversion over 4 metros, 3 days, peaking at 40.3 µg/m³ near Tampa.
Reviewed source 2
Origin: North Carolina and neighboring states
84.5 µg/m³ peak ≈ 4.3 cigarettes per person 8.6M people affected 2 city records set, 5 top-ten days
Wildfire smoke over 7 metros, 3 days, peaking at 84.5 µg/m³ near Charlotte. 2 metros set an all-time record. Origin traced to North Carolina and neighboring states.
EPA AQS 10Agency/press 1
78.8 µg/m³ peak ≈ 4.9 cigarettes per person 8.0M people affected 3 top-ten days
Wildfire smoke over 3 metros, 4 days, peaking at 78.8 µg/m³ near Atlanta.
EPA AQS 4
48.2 µg/m³ peak ≈ 1.6 cigarettes per person 2.3M people affected
Wildfire smoke over Cincinnati, 1 day, peaking at 48.2 µg/m³ near Cincinnati.
71.6 µg/m³ peak ≈ 3.8 cigarettes per person 1.8M people affected 2 top-ten days
Wildfire smoke over 2 metros, 2 days, peaking at 71.6 µg/m³ near Chattanooga.
42 µg/m³ peak ≈ 1.5 cigarettes per person 6.5M people affected
Regional secondary PM over Miami, 1 day, peaking at 42 µg/m³ near Miami.
Reviewed source 1
29.3 µg/m³ peak ≈ 1.0 cigarettes per person 853k people affected
Stagnant pollution mixture over Lakeland, 1 day, peaking at 29.3 µg/m³ near Lakeland.
Reviewed source 3
75.3 µg/m³ peak ≈ 4.8 cigarettes per person 3.4M people affected 1 top-ten day
Stagnant pollution mixture over Tampa, 2 days, peaking at 75.3 µg/m³ near Tampa.
Reviewed source 2
38.5 µg/m³ peak ≈ 1.4 cigarettes per person 1.8M people affected
Temperature inversion over Jacksonville, 1 day, peaking at 38.5 µg/m³ near Jacksonville.
Reviewed source 2
40.8 µg/m³ peak ≈ 1.4 cigarettes per person 2.2M people affected
Regional secondary PM over Nashville, 1 day, peaking at 40.8 µg/m³ near Nashville.
Reviewed source 3
77.7 µg/m³ peak ≈ 5.4 cigarettes per person 20M people affected 1 top-ten day
Regional secondary PM over New York, 2 days, peaking at 77.7 µg/m³ near New York.
Reviewed source 5
57 µg/m³ peak ≈ 2.0 cigarettes per person 9.0M people affected 1 top-ten day
Wildfire smoke over 4 metros, 2 days, peaking at 57 µg/m³ near Knoxville.
53.4 µg/m³ peak ≈ 1.9 cigarettes per person 2.9M people affected
Stagnant pollution mixture over Baltimore, 1 day, peaking at 53.4 µg/m³ near Baltimore.
55.2 µg/m³ peak ≈ 3.8 cigarettes per person 822k people affected 1 top-ten day
Stagnant pollution mixture over Dayton, 2 days, peaking at 55.2 µg/m³ near Dayton.
Reviewed source 3
50.4 µg/m³ peak ≈ 1.8 cigarettes per person 958k people affected
Regional secondary PM over Knoxville, 1 day, peaking at 50.4 µg/m³ near Knoxville.
47 µg/m³ peak ≈ 1.7 cigarettes per person 588k people affected
Stagnant pollution mixture over Chattanooga, 1 day, peaking at 47 µg/m³ near Chattanooga.
Reviewed source 2
75.2 µg/m³ peak ≈ 11.1 cigarettes per person 1.2M people affected 1 city record set
Stagnant pollution mixture over Birmingham, 5 days, peaking at 75.2 µg/m³ near Birmingham. 1 metro set an all-time record.
Reviewed source 4
52.4 µg/m³ peak ≈ 1.9 cigarettes per person 2.2M people affected 1 top-ten day
Regional secondary PM over Nashville, 1 day, peaking at 52.4 µg/m³ near Nashville.
Reviewed source 1
92.5 µg/m³ peak ≈ 3.4 cigarettes per person 14M people affected
Temperature inversion over 2 metros, 2 days, peaking at 92.5 µg/m³ near Los Angeles.
Reviewed source 2
37.9 µg/m³ peak ≈ 1.3 cigarettes per person 966k people affected
Wildfire smoke over New Orleans, 1 day, peaking at 37.9 µg/m³ near New Orleans.
Reviewed source 2
119.6 µg/m³ peak ≈ 8.5 cigarettes per person 4.7M people affected 1 top-ten day
Temperature inversion over Riverside, 3 days, peaking at 119.6 µg/m³ near Riverside.
84.4 µg/m³ peak ≈ 6.6 cigarettes per person 13M people affected
Regional secondary PM over Los Angeles, 3 days, peaking at 84.4 µg/m³ near Los Angeles.
Reviewed source 3
42.4 µg/m³ peak ≈ 3.0 cigarettes per person 835k people affected
Wildfire smoke over Oxnard, 3 days, peaking at 42.4 µg/m³ near Oxnard.
Reviewed source 3
24.8 µg/m³ peak ≈ 0.8 cigarettes per person 861k people affected 1 top-ten day
Temperature inversion over Cape Coral, 1 day, peaking at 24.8 µg/m³ near Cape Coral.
Reviewed source 1
89.8 µg/m³ peak ≈ 3.3 cigarettes per person 4.7M people affected
Regional secondary PM over Riverside, 1 day, peaking at 89.8 µg/m³ near Riverside.
46.8 µg/m³ peak ≈ 1.6 cigarettes per person 7.8M people affected 1 top-ten day
Wildfire smoke over Houston, 1 day, peaking at 46.8 µg/m³ near Houston.
48.2 µg/m³ peak ≈ 3.2 cigarettes per person 966k people affected 1 top-ten day
Wildfire smoke over New Orleans, 2 days, peaking at 48.2 µg/m³ near New Orleans.
Reviewed source 3
34.2 µg/m³ peak ≈ 1.2 cigarettes per person 2.9M people affected
Wildfire smoke over Orlando, 1 day, peaking at 34.2 µg/m³ near Orlando.
Reviewed source 2
50.6 µg/m³ peak ≈ 1.7 cigarettes per person 1.4M people affected
Regional secondary PM over Louisville/Jefferson County, 1 day, peaking at 50.6 µg/m³ near Louisville/Jefferson County.
Reviewed source 4
103.7 µg/m³ peak ≈ 4.4 cigarettes per person 2.5M people affected 1 top-ten day
Fireworks over Portland, 1 day, peaking at 103.7 µg/m³ near Portland.
39.2 µg/m³ peak ≈ 1.3 cigarettes per person 997k people affected
Fireworks over Greenville, 1 day, peaking at 39.2 µg/m³ near Greenville.
56.8 µg/m³ peak ≈ 2.0 cigarettes per person 6.3M people affected
Stagnant pollution mixture over Philadelphia, 1 day, peaking at 56.8 µg/m³ near Philadelphia.
Reviewed source 1Agency/press 1
32.6 µg/m³ peak ≈ 1.1 cigarettes per person 2.9M people affected
Wildfire smoke over Orlando, 1 day, peaking at 32.6 µg/m³ near Orlando.
Reviewed source 2
89.2 µg/m³ peak ≈ 3.3 cigarettes per person 4.7M people affected
Temperature inversion over Riverside, 1 day, peaking at 89.2 µg/m³ near Riverside.
65.2 µg/m³ peak ≈ 2.4 cigarettes per person 2.2M people affected 1 top-ten day
Stagnant pollution mixture over Cleveland, 1 day, peaking at 65.2 µg/m³ near Cleveland.
Reviewed source 3
49.6 µg/m³ peak ≈ 1.7 cigarettes per person 3.1M people affected
Mixed causes over 4 metros, 1 day, peaking at 49.6 µg/m³ near Albany.
Reviewed source 3
34.2 µg/m³ peak ≈ 1.2 cigarettes per person 2.9M people affected
Wildfire smoke over Orlando, 1 day, peaking at 34.2 µg/m³ near Orlando.
Reviewed source 1
78.5 µg/m³ peak ≈ 5.5 cigarettes per person 2.4M people affected
Regional secondary PM over Pittsburgh, 2 days, peaking at 78.5 µg/m³ near Pittsburgh.
Reviewed source 5
49.7 µg/m³ peak ≈ 3.3 cigarettes per person 2.3M people affected
Temperature inversion over Cincinnati, 2 days, peaking at 49.7 µg/m³ near Cincinnati.
Reviewed source 3
Origin: San Joaquin Valley, California
160 µg/m³ peak ≈ 8.5 cigarettes per person 2.1M people affected 1 top-ten day
Other over 2 metros, 4 days, peaking at 160 µg/m³ near Fresno. Origin traced to San Joaquin Valley, California.
Agency/press 2
71.3 µg/m³ peak ≈ 2.7 cigarettes per person 2.0M people affected
Temperature inversion over 2 metros, 1 day, peaking at 71.3 µg/m³ near Salt Lake City.
62.3 µg/m³ peak ≈ 2.3 cigarettes per person 3.5M people affected 1 top-ten day
Fireworks over 2 metros, 1 day, peaking at 62.3 µg/m³ near Baltimore.
58 µg/m³ peak ≈ 2.2 cigarettes per person 2.6M people affected 1 top-ten day
Fireworks over Austin, 1 day, peaking at 58 µg/m³ near Austin.
53.7 µg/m³ peak ≈ 1.7 cigarettes per person 6.3M people affected 3 top-ten days
Fireworks over 5 metros, 1 day, peaking at 53.7 µg/m³ near Columbia.
Reviewed source 4 1
53.3 µg/m³ peak ≈ 1.9 cigarettes per person 588k people affected 1 top-ten day
Fireworks over Chattanooga, 1 day, peaking at 53.3 µg/m³ near Chattanooga.
52.8 µg/m³ peak ≈ 1.8 cigarettes per person 3.7M people affected 3 top-ten days
Fireworks over 4 metros, 1 day, peaking at 52.8 µg/m³ near Raleigh.
35.8 µg/m³ peak ≈ 1.2 cigarettes per person 6.4M people affected
Fireworks over 2 metros, 1 day, peaking at 35.8 µg/m³ near Tampa.
Reviewed source 1
136 µg/m³ peak ≈ 5.6 cigarettes per person 1.2M people affected 1 top-ten day
Regional secondary PM over Fresno, 1 day, peaking at 136 µg/m³ near Fresno.
Reviewed source 1Agency/press 1
105 µg/m³ peak ≈ 8.3 cigarettes per person 999k people affected 1 top-ten day
Fireworks over Urban Honolulu, 2 days, peaking at 105 µg/m³ near Urban Honolulu.
EPA AQS 2Agency/press 2
59.6 µg/m³ peak ≈ 2.4 cigarettes per person 4.6M people affected 3 top-ten days
Fireworks over 5 metros, 2 days, peaking at 59.6 µg/m³ near New Haven.
39.9 µg/m³ peak ≈ 1.4 cigarettes per person 2.4M people affected
Fireworks over Las Vegas, 1 day, peaking at 39.9 µg/m³ near Las Vegas.
77 µg/m³ peak ≈ 3.1 cigarettes per person 2.0M people affected
Temperature inversion over San Jose, 1 day, peaking at 77 µg/m³ near San Jose.
66.9 µg/m³ peak ≈ 2.6 cigarettes per person 2.0M people affected
Stagnant pollution mixture over San Jose, 1 day, peaking at 66.9 µg/m³ near San Jose.
Reviewed source 2Agency/press 1
134.1 µg/m³ peak ≈ 9.5 cigarettes per person 5.4M people affected 1 top-ten day
Regional secondary PM over 4 metros, 6 days, peaking at 134.1 µg/m³ near Bakersfield.
Reviewed source 1Agency/press 1
119 µg/m³ peak ≈ 4.1 cigarettes per person 2.0M people affected
Regional secondary PM over 2 metros, 2 days, peaking at 119 µg/m³ near Fresno.
Reviewed source 1Agency/press 1
120 µg/m³ peak ≈ 9.6 cigarettes per person 1.2M people affected
Stagnant pollution mixture over Fresno, 2 days, peaking at 120 µg/m³ near Fresno.
Reviewed source 2Agency/press 1
56.3 µg/m³ peak ≈ 2.0 cigarettes per person 1.2M people affected
Temperature inversion over Birmingham, 1 day, peaking at 56.3 µg/m³ near Birmingham.
Reviewed source 3
134.8 µg/m³ peak ≈ 9.2 cigarettes per person 2.1M people affected 1 top-ten day
Other over 2 metros, 3 days, peaking at 134.8 µg/m³ near Bakersfield.
Agency/press 1
121.4 µg/m³ peak ≈ 3.4 cigarettes per person 19M people affected 1 city record set, 2 top-ten days
Temperature inversion over 3 metros, 1 day, peaking at 121.4 µg/m³ near Riverside. 1 metro set an all-time record.
Reviewed source 2
62.4 µg/m³ peak ≈ 4.4 cigarettes per person 1.2M people affected 1 top-ten day
Wildfire smoke over Birmingham, 2 days, peaking at 62.4 µg/m³ near Birmingham.
Reviewed source 2
90 µg/m³ peak ≈ 3.3 cigarettes per person 4.5M people affected
Wildfire smoke over 2 metros, 2 days, peaking at 90 µg/m³ near Sacramento.
38.6 µg/m³ peak ≈ 1.2 cigarettes per person 769k people affected
Temperature inversion over Little Rock, 1 day, peaking at 38.6 µg/m³ near Little Rock.
Reviewed source 3
157.1 µg/m³ peak ≈ 6.7 cigarettes per person 2.2M people affected 1 top-ten day
Other over Columbus, 1 day, peaking at 157.1 µg/m³ near Columbus.
67 µg/m³ peak ≈ 2.5 cigarettes per person 6.4M people affected 1 top-ten day
Stagnant pollution mixture over Washington, 1 day, peaking at 67 µg/m³ near Washington.
Reviewed source 1
42.9 µg/m³ peak ≈ 2.9 cigarettes per person 1.3M people affected
Stagnant pollution mixture over Memphis, 2 days, peaking at 42.9 µg/m³ near Memphis.
Reviewed source 3
108 µg/m³ peak ≈ 4.5 cigarettes per person 2.5M people affected
Wildfire smoke over Sacramento, 1 day, peaking at 108 µg/m³ near Sacramento.
58.3 µg/m³ peak ≈ 2.1 cigarettes per person 1.2M people affected
Temperature inversion over Birmingham, 1 day, peaking at 58.3 µg/m³ near Birmingham.
Reviewed source 3
59.1 µg/m³ peak ≈ 2.1 cigarettes per person 6.4M people affected
Stagnant pollution mixture over Atlanta, 1 day, peaking at 59.1 µg/m³ near Atlanta.
Reviewed source 1Agency/press 1
44.8 µg/m³ peak ≈ 1.5 cigarettes per person 4.4M people affected 1 top-ten day
Stagnant pollution mixture over 3 metros, 2 days, peaking at 44.8 µg/m³ near Winston.
Reviewed source 2
53.3 µg/m³ peak ≈ 1.8 cigarettes per person 6.4M people affected
Stagnant pollution mixture over Atlanta, 1 day, peaking at 53.3 µg/m³ near Atlanta.
Reviewed source 1Agency/press 1
45.5 µg/m³ peak ≈ 1.6 cigarettes per person 606k people affected 1 top-ten day
Temperature inversion over Jackson, 1 day, peaking at 45.5 µg/m³ near Jackson.
Reviewed source 3
41.1 µg/m³ peak ≈ 1.4 cigarettes per person 2.9M people affected
Regional secondary PM over Charlotte, 1 day, peaking at 41.1 µg/m³ near Charlotte.
Reviewed source 4
61.6 µg/m³ peak ≈ 2.2 cigarettes per person 6.4M people affected
Stagnant pollution mixture over Atlanta, 1 day, peaking at 61.6 µg/m³ near Atlanta.
Reviewed source 2Agency/press 1
54.5 µg/m³ peak ≈ 1.9 cigarettes per person 1.2M people affected
Stagnant pollution mixture over Birmingham, 1 day, peaking at 54.5 µg/m³ near Birmingham.
Reviewed source 3
41.2 µg/m³ peak ≈ 1.4 cigarettes per person 2.9M people affected
Stagnant pollution mixture over Charlotte, 1 day, peaking at 41.2 µg/m³ near Charlotte.
39.8 µg/m³ peak ≈ 1.4 cigarettes per person 801k people affected
Stagnant pollution mixture over Greensboro, 1 day, peaking at 39.8 µg/m³ near Greensboro.
38.2 µg/m³ peak ≈ 1.3 cigarettes per person 870k people affected
Stagnant pollution mixture over Columbia, 1 day, peaking at 38.2 µg/m³ near Columbia.
37.1 µg/m³ peak ≈ 1.3 cigarettes per person 621k people affected
Stagnant pollution mixture over Durham, 1 day, peaking at 37.1 µg/m³ near Durham.
56.3 µg/m³ peak ≈ 2.1 cigarettes per person 6.4M people affected
Stagnant pollution mixture over Washington, 1 day, peaking at 56.3 µg/m³ near Washington.
Reviewed source 1
54.3 µg/m³ peak ≈ 2.3 cigarettes per person 11M people affected 4 top-ten days
Regional secondary PM over 7 metros, 2 days, peaking at 54.3 µg/m³ near Boston.
Agency/press 1Reviewed source 1
72.8 µg/m³ peak ≈ 2.4 cigarettes per person 14M people affected 3 top-ten days
Regional secondary PM over 10 metros, 4 days, peaking at 72.8 µg/m³ near Pittsburgh.
Reviewed source 2Agency/press 1
55.1 µg/m³ peak ≈ 1.9 cigarettes per person 1.2M people affected
Regional secondary PM over Birmingham, 1 day, peaking at 55.1 µg/m³ near Birmingham.
Reviewed source 3
48.5 µg/m³ peak ≈ 1.8 cigarettes per person 1.4M people affected 1 top-ten day
Stagnant pollution mixture over Richmond, 1 day, peaking at 48.5 µg/m³ near Richmond.
85.6 µg/m³ peak ≈ 3.2 cigarettes per person 13M people affected
Fireworks over Los Angeles, 1 day, peaking at 85.6 µg/m³ near Los Angeles.
55.8 µg/m³ peak ≈ 2.1 cigarettes per person 2.2M people affected 1 top-ten day
Fireworks over Nashville, 1 day, peaking at 55.8 µg/m³ near Nashville.
72.1 µg/m³ peak ≈ 2.8 cigarettes per person 6.4M people affected 1 top-ten day
Prescribed fire over Washington, 1 day, peaking at 72.1 µg/m³ near Washington.
59 µg/m³ peak ≈ 2.1 cigarettes per person 2.9M people affected 1 top-ten day
Regional secondary PM over 2 metros, 1 day, peaking at 59 µg/m³ near Cleveland.
Reviewed source 6
56.9 µg/m³ peak ≈ 2.0 cigarettes per person 2.3M people affected 1 top-ten day
Stagnant pollution mixture over Cincinnati, 1 day, peaking at 56.9 µg/m³ near Cincinnati.
Reviewed source 3
47.4 µg/m³ peak ≈ 1.7 cigarettes per person 2.2M people affected 1 top-ten day
Stagnant pollution mixture over Nashville, 1 day, peaking at 47.4 µg/m³ near Nashville.
Reviewed source 3
Named source Palm Beach County brush fire · Palm Beach County, Florida
46.9 µg/m³ peak ≈ 1.7 cigarettes per person 6.5M people affected
Wildfire smoke over Miami, 1 day, peaking at 46.9 µg/m³ near Miami. Origin traced to Palm Beach County, Florida.
NOAA 1
58.4 µg/m³ peak ≈ 2.1 cigarettes per person 958k people affected
Regional secondary PM over Knoxville, 1 day, peaking at 58.4 µg/m³ near Knoxville.
72.7 µg/m³ peak ≈ 2.8 cigarettes per person 958k people affected 1 top-ten day
Stagnant pollution mixture over Knoxville, 1 day, peaking at 72.7 µg/m³ near Knoxville.
Reviewed source 2
97.9 µg/m³ peak ≈ 3.7 cigarettes per person 4.7M people affected 1 top-ten day
Temperature inversion over Riverside, 1 day, peaking at 97.9 µg/m³ near Riverside.
81.3 µg/m³ peak ≈ 3.0 cigarettes per person 13M people affected
Temperature inversion over Los Angeles, 1 day, peaking at 81.3 µg/m³ near Los Angeles.
68.3 µg/m³ peak ≈ 2.5 cigarettes per person 6.4M people affected 1 top-ten day
Temperature inversion over Atlanta, 1 day, peaking at 68.3 µg/m³ near Atlanta.
Reviewed source 3
128 µg/m³ peak ≈ 5.3 cigarettes per person 1.2M people affected
Stagnant pollution mixture over Fresno, 1 day, peaking at 128 µg/m³ near Fresno.
Reviewed source 2
86 µg/m³ peak ≈ 3.5 cigarettes per person 816k people affected
Stagnant pollution mixture over Stockton, 1 day, peaking at 86 µg/m³ near Stockton.
Reviewed source 2
56.1 µg/m³ peak ≈ 2.2 cigarettes per person 846k people affected
Temperature inversion over Boise City, 1 day, peaking at 56.1 µg/m³ near Boise City.
Reviewed source 4
71 µg/m³ peak ≈ 5.1 cigarettes per person 2.5M people affected
Temperature inversion over Portland, 2 days, peaking at 71 µg/m³ near Portland.
Reviewed source 4
73.1 µg/m³ peak ≈ 3.1 cigarettes per person 999k people affected 1 top-ten day
Other over Urban Honolulu, 1 day, peaking at 73.1 µg/m³ near Urban Honolulu.
No air events match. Clear the search or pick a different cause.
425 working episodes remain attached to their individual city records. They are real monitor observations, but IAQng does not promote them into this causal-event catalog until retained evidence supports the event boundary and cause. “Unknown” means unknown—not “no smoke,” “no dust,” or proof that simultaneous cities shared one event.
For discovery, nearby local episodes may still share an internal observation-cluster ID. That is a search convenience only. It is never displayed as evidence that the places experienced one regional event.
Episodes start as elevated-PM2.5 candidates in the monitor record (the same data behind the city rankings). Evidence is then gathered per candidate: agency and health-department statements, NOAA Storm Events records, and link-first news coverage. A resolution pass groups candidates into one named episode only when the retained evidence supports the same real-world source, and records its reasoning and uncertainties; everything else stays unattributed.
What can merge episodes. Retained evidence that they share one real-world source occurrence: overlapping timing with a plausible progression, compatible origin regions, and corroborating official or news records. The resolution pass must cite the evidence it used, by ID.
What can never merge them. Severity alone, proximity alone, the season, article counts, or a shared cause label without connecting evidence. No PM2.5 threshold is treated as proof of any cause.
The three outcomes. Resolve into a named regional episode; abstain, leaving each local episode unattributed (unknown means unknown, not "no smoke"); or record a dispute and keep the candidates separate.
Evidence roles. Official assessments carry the most weight, then corroboration, hypothesis, and context. Counts are never a credibility score: one agency determination outweighs any number of headlines.
What changes a record. EPA certifying provisional days, new qualified evidence, or editorial review. No record here is final, and a correction is the fastest way to change one.
Grouping policy common_sense_root_cause_grouping.v2, resolved Jul 24, 2026 · working events pm25-unresolved-multimetro-local-episode-overlay.v1 (1444 records; frozen baseline 1265) · news evidence news-evidence-candidates.v1 (1786 items) · official matches pm25-official-source-matches.v2 (56 records). Attribution is automated grouping over retained evidence, not per-episode editorial sign-off. See editorial standards.