Wildfire smoke Corroborated
Daily PM2.5 peaked at 59.2 µg/m³ near Lakeland across 3 covered metros home to 4.7 million people. 3 metros placed a top-ten day in their record.
Counting the extra PM2.5 above each metro's typical day, this event handed the average affected resident ≈ 1.7 cigarettes. Across everyone living in the affected metros, that is the collective equivalent of ≈ 8.2 million cigarettes. An awareness illustration of outdoor exposure at 22 µg/m³ per cigarette (Berkeley Earth), counting only the event's ranked days; not a medical dose.
Why we think this happened
The frozen baseline classifies this event as wildfire smoke, and the retained NOAA, Florida legislative, and scientific records consistently document the contemporaneous Polk City-Lakeland wildfire and smoke occurrence.
Corroborated Independent reporting agrees on the cause, with no agency determination, monitor flag, or published assessment behind it.
American Meteorological Society corroborates
This meteorological conference paper describes a February 18–24, 2001 northern Polk County wildfire, reporting that it burned along and north of the I-4 corridor and closed a section of I-4 between Polk City and Lakeland because of wildfire conditions. It corroborates the nearby wildfire timing but does not establish attribution for the PM2.5 observations.
Florida Legislature · Jan 10, 2002 corroborates
A Florida legislative record lists a federal fire-suppression-assistance grant for the Lakeland Fire District dated February 18, 2001, corroborating a significant Lakeland-area wildfire at the end of this event window; it does not attribute PM2.5 concentrations to the fire.
National Oceanic and Atmospheric Administration hypothesis
NOAA's monthly Storm Data narrative reports a February 17 wildfire near the Polk City–Lakeland section of Interstate 4 and a variable smoke plume that reduced visibility. It documents a local smoke source during the event window, but does not attribute the listed PM2.5 observations, including Orlando, to that fire.
See every retained source and limitation ↓
Sequence: Orlando (Feb 17) → Lakeland (Feb 18) → North Port (Feb 18)
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
The catalog has a grouping hypothesis, but no retained source directly establishes the proposed cause.
Air-mass movement
This meteorological conference paper describes a February 18–24, 2001 northern Polk County wildfire, reporting that it burned along and north of the I-4 corridor and closed a section of I-4 between Polk City and Lakeland because of wildfire…
View transport source ↗Local response
EPA monitors recorded the event across 3 metros. The peak daily concentration is roughly 2.7 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.
Orlando-Kissimmee-Sanford, FL
Monitor comparison window 2001-02-14 to 2001-02-21 · PM2.5 target: Primrose Ave
73% above nearby days
29% lower than surrounding days
73% higher than surrounding days
29% lower than surrounding days
10% lower than surrounding days
30% lower than surrounding days
208% higher than surrounding days
24% higher than surrounding days
Lakeland-Winter Haven, FL
Monitor comparison window 2001-02-14 to 2001-02-21 · PM2.5 target: Baptist Childrens' Home
415% above nearby days
104% higher than surrounding days
415% higher than surrounding days
104% higher than surrounding days
91% higher than surrounding days
15% higher than surrounding days
North Port-Sarasota-Bradenton, FL
Monitor comparison window 2001-02-14 to 2001-02-21 · PM2.5 target: G.T. BRAY PARK
458% above nearby days
22% higher than surrounding days
458% higher than surrounding days
22% higher than surrounding days
19% lower than surrounding days
57% lower than surrounding days
400% higher than surrounding days
33% higher than 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 · 2001-02-18
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.
Air arriving near North Port-Sarasota-Bradenton
Peak-date arrivals · 2001-02-18
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.
Air arriving near Orlando-Kissimmee-Sanford
Peak-date arrivals · 2001-02-17
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 | 59.2 µg/m³ | 2.7 | Feb 18, 2001 | #2 of its top days |
| North Port-Sarasota-Bradenton, FL | 48 µg/m³ | 2.2 | Feb 18, 2001 | #2 of its top days |
| Orlando-Kissimmee-Sanford, FL | 40.7 µg/m³ | 1.9 | Feb 17, 2001 | #6 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.
Legislative Budget Commission Meeting
A Florida legislative record lists a federal fire-suppression-assistance grant for the Lakeland Fire District dated February 18, 2001, corroborating a significant Lakeland-area wildfire at the end of this event window; it does not attribute PM2.5 concentrations to the fire.
Central Florida Super Fog - Carnage on Interstate -4
This meteorological conference paper describes a February 18–24, 2001 northern Polk County wildfire, reporting that it burned along and north of the I-4 corridor and closed a section of I-4 between Polk City and Lakeland because of wildfire conditions. It corroborates the nearby wildfire timing but does not establish attribution for the PM2.5 observations.
February 2001 Storm Data and Unusual Weather Phenomena
NOAA's monthly Storm Data narrative reports a February 17 wildfire near the Polk City–Lakeland section of Interstate 4 and a variable smoke plume that reduced visibility. It documents a local smoke source during the event window, but does not attribute the listed PM2.5 observations, including Orlando, to that fire.
Cited authorities: National Oceanic and Atmospheric Administration
Corroborated Independent reporting agrees on the cause, with no agency determination, monitor flag, or published assessment behind it.
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.