Wildfire smoke Officially verified
Daily PM2.5 peaked at 25.9 µg/m³ near Lakeland across 1 covered metro home to 852,878 people.
Why we think this happened
Exact-date NWS and NOAA Storm Data records directly connect Polk County and Lakeland-area visibility impacts to the active wildfire; contemporaneous reporting identifies it as the Stagecoach Fire.
Officially verified A directly applicable government determination or qualified scientific attribution product identifies this cause.
NOAA National Centers for Environmental Information · Feb 28, 2001 official
NOAA Storm Data records a Polk County wildfire from February 18 through 24 that burned about 11,000 acres, repeatedly closed Interstate 4 between Polk City and Lakeland, and produced smoke and ash across central Florida.
National Weather Service Tampa Bay Area via Iowa Environmental Mesonet · Feb 24, 2001 official
NWS Tampa Bay said low smoke would mix out during the afternoon except in Polk County, where areas closest to the fire would continue to have reduced visibility.
Associated Press via New Haven Register · Feb 25, 2001 hypothesis
Contemporaneous Associated Press reporting names the roughly 10,000-acre Polk County blaze as the Stagecoach Fire and reports that it was still active at the end of the catalog window.
Evidence path
A cause is more convincing when the record connects three things: something happened, the air mass moved toward the region, and local instruments responded. Here is how much of that chain is documented for this event.
Source or mechanism
NOAA Storm Data records a Polk County wildfire from February 18 through 24 that burned about 11,000 acres, repeatedly closed Interstate 4 between Polk City and Lakeland, and produced smoke and ash across central Florida.
View supporting source ↗Air-mass movement
NOAA HYSPLIT modeled 12 backward paths across multiple arrival times and heights. They show where the air traveled, not which source polluted it.
Explore the modeled paths ↓Local response
EPA monitors recorded the event across 1 metro. The peak daily concentration is roughly 1.2 cigarette-equivalents at the outdoor daily rate.
Inspect the pollutant and weather signals ↓Event autopsy
Before, during, and after the episode: nearby pollutant monitors and surface-weather stations show what changed. This context tests the “Wildfire smoke” explanation; it does not assign the cause by itself.
Lakeland-Winter Haven, FL
Monitor comparison window 2001-02-21 to 2001-02-27 · PM2.5 target: Baptist Childrens' Home
125% above nearby days
19% higher than surrounding days
125% higher than surrounding days
19% higher than surrounding days
37% lower than surrounding days
About the same as surrounding days
Source: U.S. EPA AirData daily observations and, where available, nearby ASOS/AWOS surface observations. Values are descriptive medians over the retained monitor set; missing measurements remain missing. Transport and source evidence remain separate layers because this instrument pattern does not assign a cause by itself.
Air-mass reconstruction
NOAA HYSPLIT traces the air arriving at each metro backward for 72 hours. Multiple arrival times and heights show whether the broad path is stable—or sensitive to assumptions about when and where the polluted layer arrived.
Air arriving near Lakeland-Winter Haven
Peak-date arrivals · 2001-02-24
Each line begins 72 hours before arrival and points toward the metro. Color represents arrival height; repeated lines represent 00, 06, 12, and 18 UTC arrival assumptions. A path can show where the air traveled, but it cannot prove which source added the PM2.5.
Episode peak
-- cigarettes
The smoke map's scale, replayed over this event: the surface interpolates between covered metros' daily records, framed to the affected region. Hover for a reading, click a metro to pin it to the card. Days a monitor did not report draw nothing.
Views from the selected metro
Select a metro on the map to see nearby cameras. Where an operator archive reaches the event, drag the divider to compare two moments, adjust either date and time, or play the available event-day frames. Camera imagery is visual context, not an air-quality measurement or proof of smoke.
No useful public camera views are currently available within 80 km of this metro.
| Metro | Peak PM2.5 | Cigarettes, whole event | Peak day | All-time standing |
|---|---|---|---|---|
| Lakeland-Winter Haven, FL | 25.9 µg/m³ | 1.2 | Feb 24, 2001 | #17 of its top days |
"Cigarettes, whole event" totals a metro's ranked event days at 22 µg/m³ per cigarette: what a person outdoors there breathed across the event, as the illustration. "All-time standing" is where this episode's days sit in each metro's ranked record (worst-area measure, since 1999). Full local context is on each metro's Air Records page.
Public evidence library
Each card states what a source supports—and what it does not. Official records, research, reporting, community observations, and transparent inferences remain visibly different kinds of evidence.
NOAA National Centers for Environmental Information
NOAA Storm Data records a Polk County wildfire from February 18 through 24 that burned about 11,000 acres, repeatedly closed Interstate 4 between Polk City and Lakeland, and produced smoke and ash across central Florida.
An official source supports the attributed cause for the stated place and dates.
Storm Data describes the county-scale incident rather than apportioning the Lakeland monitor's daily PM2.5 mass.
NOAA/NWS surface observations via Iowa Environmental Mesonet
LAKELAND REGIONAL, 6.4 km from the PM2.5 target monitor, reported the official present-weather code FU (smoke) during 5 observed hours inside the catalog event window.
This source supports a possible mechanism or occurrence; it does not establish the cause by itself.
The surface code establishes smoke at the nearby airport; it does not identify whether the source was a wildfire, prescribed burn, agricultural fire, or another local fire.
National Weather Service Tampa Bay Area via Iowa Environmental Mesonet
NWS Tampa Bay said low smoke would mix out during the afternoon except in Polk County, where areas closest to the fire would continue to have reduced visibility.
An official source supports the attributed cause for the stated place and dates.
The discussion identifies a Polk County fire and its smoke but does not name the fire.
Associated Press via New Haven Register
Contemporaneous Associated Press reporting names the roughly 10,000-acre Polk County blaze as the Stagecoach Fire and reports that it was still active at the end of the catalog window.
This source supports a possible mechanism or occurrence; it does not establish the cause by itself.
The article names the fire but the official NWS and Storm Data records provide the direct smoke attribution.
Officially verified A directly applicable government determination or qualified scientific attribution product identifies this cause.
This episode was grouped from the monitor record by the catalog pipeline and given its cause from the evidence listed above. It has not been individually reviewed and signed off, so its boundaries, cause, and name may change as evidence accumulates. Grouping policy common_sense_root_cause_grouping.v2. The cause label reflects the assembled evidence above, not an IAQng detection formula. If it is wrong, tell us.