Fireworks Corroborated provisional
Daily PM2.5 peaked at 51 µg/m³ near Miami across 1 covered metro home to 6.5 million people. 1 metro 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 ≈ 1.9 cigarettes. Across everyone living in the affected metros, that is the collective equivalent of ≈ 12 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 supplied retained evidence supports fireworks for this event; no supplied evidence establishes membership in a broader time-bounded episode.
Corroborated Independent reporting agrees on the cause, with no agency determination, monitor flag, or published assessment behind it.
Local 10 News · Jul 5, 2026 corroborates
A South Florida meteorologist reported that July 4 fireworks left substantial smoke and an air-quality alert in effect for Broward County; this materially supports fireworks smoke affecting the Miami metropolitan event.
WPBF 25 News · Jul 5, 2026 corroborates
The report said smoke and debris from July 4 fireworks created haze across southeast Florida and quoted a National Weather Service statement forecasting elevated fine-particle concentrations in Miami-Dade, Broward, and Palm Beach counties.
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
A South Florida meteorologist reported that July 4 fireworks left substantial smoke and an air-quality alert in effect for Broward County; this materially supports fireworks smoke affecting the Miami metropolitan event.
View supporting source ↗Air-mass movement
The report said smoke and debris from July 4 fireworks created haze across southeast Florida and quoted a National Weather Service statement forecasting elevated fine-particle concentrations in Miami-Dade, Broward, and Palm Beach counties.
View transport source ↗Local response
EPA monitors recorded the event across 1 metro. The peak daily concentration is roughly 2.3 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 “Fireworks” explanation; it does not assign the cause by itself.
Miami-Fort Lauderdale-West Palm Beach, FL
Monitor comparison window 2026-07-02 to 2026-07-08
The PM2.5 event remains in the catalog, but the surrounding monitoring record cannot supply a defensible instrument fingerprint for this place and date.
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.
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.
| Metro | Peak PM2.5 | Cigarettes, whole event | Peak day | All-time standing |
|---|---|---|---|---|
| Miami-Fort Lauderdale-West Palm Beach, FL | 51 µg/m³ | 2.3 | Jul 5, 2026 | #8 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.
A South Florida meteorologist reported that July 4 fireworks left substantial smoke and an air-quality alert in effect for Broward County; this materially supports fireworks smoke affecting the Miami metropolitan event.
Fireworks debris creates haze over South Florida
The report said smoke and debris from July 4 fireworks created haze across southeast Florida and quoted a National Weather Service statement forecasting elevated fine-particle concentrations in Miami-Dade, Broward, and Palm Beach counties.
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. Recent days are preliminary AirNow readings and re-rank once EPA certifies them. 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.