Wildfire smoke
August 3–5, 2025 Northeast Canadian wildfire-smoke episode
Daily PM2.5 peaked at 51.5 µg/m³ near Buffalo across 4 covered metros home to 3.8 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 ≈ 6.1 cigarettes. Across everyone living in the affected metros, that is the collective equivalent of ≈ 23 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.
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.
What happened, in the record
The supplied evidence supports wildfire smoke and documents an overlapping or continuing regional occurrence across the proposed members. The supplied evidence supports wildfire smoke and documents an overlapping or continuing regional occurrence across the proposed members.
Sequence: Rochester (Aug 3) → Buffalo (Aug 4) → Albany (Aug 4) → Syracuse (Aug 4)
Affected metros
| Metro | Peak PM2.5 | Cigarettes, whole event | Peak day | All-time standing |
|---|---|---|---|---|
| Buffalo-Cheektowaga-Niagara Falls, NY | 51.5 µg/m³ | 8.1 | Aug 4, 2025 | #5 of its top days |
| Albany-Schenectady-Troy, NY | 48.6 µg/m³ | 4.2 | Aug 5, 2025 | #12 of its top days |
| Rochester, NY | 48.4 µg/m³ | 9.7 | Aug 4, 2025 | #7 of its top days |
| Syracuse, NY | 45.4 µg/m³ | 5.8 | Aug 4, 2025 | #9 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.
The evidence
Agency and publisher pages 1
- Governor Hochul Issues Update on Statewide Air Quality to Keep New Yorkers Safe New York's August 4 PM2.5 advisory covered Central and Western New York, Eastern Lake Ontario, and Upper Hudson Valley and attributed the particulate pollution to smoke from wildfires in Canada.
What remains uncertain
- The supplied evidence does not identify or quantify every specific source contributing across all proposed members.
Status and provenance
Research preview: this record carries research-only status and its boundaries, cause, and name may change as evidence review completes. Grouping policy common_sense_root_cause_grouping.v2. The cause label reflects the assembled evidence above, not an IAQng detection formula.