Right now
The most recent data we hold from NOAA arrived 2 minutes ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
Nothing else has been detected within 20 km in the last 24 hours.
This alert expired on 18 May 2026 at 16:15 UTC. It is kept here as a record.
It is the 35th strongest of the 103 detections recorded within 20 km of this point since 15 March 2026. Another comparable one was recorded here earlier the same day. 2 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued May 18 at 10:52AM CDT until May 18 at 11:15AM CDT by NWS Lincoln IL
An estimated 39,309 people live within 50 km of this point.
Nearby, since 15 March 2026
- July 4, 2026 · score 34 · 1.9 km
- June 8, 2026 · score 34 · 6.8 km
- July 3, 2026 · score 34 · 18.1 km
How we know
Confirmed by 4 independent sources, including NOAA.
Our own score for this event is 34 out of 100, at 91 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Computed under scoring rules v1. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | Medium |
| Calamity Score (ours) | 34 / 100 |
| Our confidence | 91% |
| Coordinates | 39.4057, -88.5143 |
| Nearest City | Mattoon (15 km) |
| Population Exposed | 39.3K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-18T15:52:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.fbc41fa700f2acd0077b2bb2334b3b80 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Clay, IL; Effingham, IL; Jasper, IL; Champaign, IL; Douglas, IL; Piatt, IL |
| Headline | Severe Thunderstorm Warning issued May 18 at 10:52AM CDT until May 18 at 11:15AM CDT by NWS Lincoln IL |
| Expires | 2026-05-18T11:15:00-05:00 |
| SenderName | NWS Lincoln IL |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.fbc41fa700f2acd0077b2bb2334b3b80f4468619.001.1","noaa_urn:oid:2.49.0.1.840.0.c40487faf2ba14c007e258c3fcfe7719bc64f3a2.002.1"] |
| Iem TypeSummary | D |
| Iem City | 1 WNW Assumption |
| Iem County | Christian |
| Iem State | IL |
| Iem Wfo | ILX |
| Iem Remark | Large tree limbs down. |
| MergedSources | [{"id":"iem_G_39.530_-89.330_1779115200000","source":"iem","severity":"low","severityValue":25,"timestamp":1779115200000,"latitude":39.53,"longitude":-89.33},{"id":"iem_H_39.420_-88.290_1779115200000","source":"iem","severity":"low","severityValue":25,"timestamp":1779115200000,"latitude":39.42,"longitude":-88.29},{"id":"iem_D_39.520_-89.060_1779112920000","source":"iem","severity":"low","severityValue":25,"timestamp":1779112920000,"latitude":39.52,"longitude":-89.06}] |
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 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 Mattoon?
Calamity.live data shows a weather event with CalamityScore 34/100, near Mattoon (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.