Reported by AIRNOW yesterday.
It is the strongest of the 33 detections recorded within 20 km of this point since 13 March 2026. The last comparable one was on 23 August 2026.
What the source measured
AIRNOW reported: AQI: 105 (Unhealthy for Sensitive Groups) · PM2.5 AQI: 63 · Ozone AQI: 105
An estimated 1,096,098 people live within 5 km of this point.
Nearby, since 13 March 2026
- May 29, 2026 · score 14 · 0.0 km
How we know
One source: AIRNOW. Not yet confirmed by a second, independent source.
Our own score for this event is 50 out of 100, at 70 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Computed under scoring rules v4. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Air Quality |
| Severity | Low |
| Calamity Score (ours) | 50 / 100 |
| Our confidence | 70% |
| Coordinates | 41.8410, -87.6745 |
| Nearest City | Lower West Side (1 km) |
| Population Exposed | 1.1M within 5 km |
| Impact Tier | minor |
| Timestamp | 2026-09-04T00:00:00.000Z |
| Source | https://www.airnow.gov/ |
Score Breakdown
Technical Details
| Aqi | 105 |
| Pm25Aqi | 63 |
| OzoneAqi | 105 |
| CategoryName | Unhealthy for Sensitive Groups |
| ReportingArea | Chicago |
| StateCode | IL |
| City | Chicago |
Safety Information
When air quality is hazardous: stay indoors with windows closed, and run a filtered air purifier if you have one. Avoid outdoor exercise. Children, older adults and anyone with heart or lung conditions are affected first and worst — an N95 respirator helps outdoors, a cloth mask does not.
Series begins 8 March 2026. Comparisons refer to that period only. Collection gap: 14-26 August 2026.
This data is aggregated algorithmically from scientific sources. Not a replacement for official emergency warnings.
Want to know when something happens near Lower West Side?
Calamity.live data shows a air quality event with CalamityScore 50/100, near Lower West Side (United States), based on data from airnow. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.