This alert expired on 16 May 2026 at 04:15 UTC. It is kept here as a record.
No stronger detection stands among the 45 recorded within 20 km of this point since 16 March 2026 — 24 others scored the same. The last comparable one was on 14 April 2026.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued May 15 at 10:24PM CDT until May 15 at 11:15PM CDT by NWS La Crosse WI
An estimated 109,715 people live within 50 km of this point.
Nearby, since 16 March 2026
- July 11, 2026 · score 43 · 4.4 km
- July 26, 2026 · score 43 · 5.3 km
- July 13, 2026 · score 43 · 7.0 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 43 out of 100, at 90 % 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) | 43 / 100 |
| Our confidence | 90% |
| Coordinates | 42.6340, -92.4440 |
| Nearest City | Cedar Falls (12 km) |
| Population Exposed | 109.7K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-16T03:24:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.9194106e7a740458d690b66fd7ccee65 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Fayette, IA; Butler, IA; Franklin, IA; Grundy, IA; Hardin, IA; Black Hawk, IA; Bremer, IA; Butler, IA |
| Headline | Severe Thunderstorm Warning issued May 15 at 10:24PM CDT until May 15 at 11:15PM CDT by NWS La Crosse WI |
| Expires | 2026-05-15T23:15:00-05:00 |
| SenderName | NWS La Crosse WI |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.9194106e7a740458d690b66fd7ccee655355b7bc.001.1","noaa_urn:oid:2.49.0.1.840.0.5fd2f53dc6916092e21769009e8b4b633363c967.001.1","noaa_urn:oid:2.49.0.1.840.0.a09930a66612b534e3e662851ed9dfbf00132180.001.1"] |
| Iem TypeSummary | G |
| Iem Magnitude | 43 |
| Iem Unit | MPH |
| Iem City | 2 N Ionia |
| Iem County | Chickasaw |
| Iem State | IA |
| Iem Wfo | ARX |
| Iem Remark | Mesonet station RNHI4 New Hampton. |
| MergedSources | [{"id":"iem_G_43.070_-92.620_1778897700000","source":"iem","severity":"low","severityValue":25,"timestamp":1778897700000,"latitude":43.07,"longitude":-92.62},{"id":"iem_G_43.070_-92.460_1778898600000","source":"iem","severity":"low","severityValue":25,"timestamp":1778898600000,"latitude":43.07,"longitude":-92.46}] |
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 Cedar Falls?
Calamity.live data shows a weather event with CalamityScore 43/100, near Cedar Falls (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.