This alert expired on 11 March 2026 at 00:45 UTC. It is kept here as a record.
It is the strongest of the 70 detections recorded within 20 km of this point since 10 March 2026.
What the source measured
NOAA reported: Special Marine Warning issued March 10 at 5:45PM CDT until March 10 at 7:45PM CDT by NWS Chicago IL
An estimated 6,279,559 people live within 50 km of this point.
Nearby, since 10 March 2026
- August 12, 2026 · score 52 · 2.1 km
- July 27, 2026 · score 52 · 2.1 km
- June 11, 2026 · score 46 · 2.4 km
How we know
Confirmed by 8 independent sources, including NOAA.
Our own score for this event is 58 out of 100, at 88 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Event Data
| Type | Severe weather |
| Severity | high |
| Calamity Score (ours) | 58 / 100 |
| Our confidence | 88% |
| Coordinates | 41.7980, -87.3395 |
| Nearest City | South Chicago (19 km) |
| Population Exposed | 6.3M within 50 km |
| Impact Tier | severe |
| Timestamp | 2026-03-10T22:45:00.000Z |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Wilmette Harbor to Northerly Island IL; Northerly Island to Calumet Harbor IL; Calumet Harbor IL to Gary IN; Gary to Burns Harbor IN; Burns Harbor to Michigan City IN; Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5NM offshore to Mid Lake; Lake Michigan from Wilmette Harbor to Michigan City in 5NM offshore to Mid Lake |
| Headline | Special Marine Warning issued March 10 at 5:45PM CDT until March 10 at 7:45PM CDT by NWS Chicago IL |
| Expires | 2026-03-10T19:45:00-05:00 |
| SenderName | NWS Chicago IL |
| HasExactCoords | true |
| Spc ReportType | hail |
| Spc Speed | 250 |
| Spc Location | 1 E Woodridge |
| Spc County | DuPage |
| Spc State | IL |
| Spc Comments | Public report of tennis ball size hail in southwest Downers Grove. (LOT) |
| MergedSources | [{"id":"spc_hail_41.64_-88.20_21","source":"spc","severity":"high","severityValue":65,"timestamp":1773180780000,"latitude":41.64,"longitude":-88.2},{"id":"spc_hail_41.68_-88.14_24","source":"spc","severity":"high","severityValue":65,"timestamp":1773181440000,"latitude":41.68,"longitude":-88.14},{"id":"spc_hail_41.69_-88.15_27","source":"spc","severity":"high","severityValue":65,"timestamp":1773181860000,"latitude":41.69,"longitude":-88.15},{"id":"spc_hail_41.69_-88.11_29","source":"spc","severity":"high","severityValue":65,"timestamp":1773182040000,"latitude":41.69,"longitude":-88.11},{"id":"spc_hail_41.75_-88.01_30","source":"spc","severity":"high","severityValue":65,"timestamp":1773182520000,"latitude":41.75,"longitude":-88.01},{"id":"spc_hail_41.75_-88.04_31","source":"spc","severity":"high","severityValue":65,"timestamp":1773182640000,"latitude":41.75,"longitude":-88.04},{"id":"spc_hail_41.76_-88.02_32","source":"spc","severity":"high","severityValue":65,"timestamp":1773183000000,"latitude":41.76,"longitude":-88.02}] |
Safety Information
Always follow official guidance from your local emergency management agency. This platform provides scientific monitoring data and is not a substitute for official warnings. If you are in immediate danger, contact your local emergency number.
Series begins 10 February 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.
Calamity.live data shows a weather event with CalamityScore 58/100, near South Chicago (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 191 scientific monitoring sources.