This alert expired on 18 May 2026 at 02:45 UTC. It is kept here as a record.
It is the 3rd strongest of the 35 detections recorded within 20 km of this point since 15 March 2026. Another comparable one was recorded here earlier the same day. 8 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued May 17 at 9:11PM CDT until May 17 at 9:45PM CDT by NWS Twin Cities/Chanhassen MN
An estimated 872,749 people live within 50 km of this point.
Nearby, since 15 March 2026
- June 6, 2026 · score 41 · 9.2 km
- July 28, 2026 · score 43 · 12.4 km
- June 11, 2026 · score 67 · 16.2 km
How we know
Confirmed by 20 independent sources, including NOAA.
Our own score for this event is 48 out of 100, at 90 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Event Data
| Type | Severe weather |
| Severity | medium |
| Calamity Score (ours) | 48 / 100 |
| Our confidence | 90% |
| Coordinates | 40.8658, -96.2056 |
| Nearest City | Papillion (35 km) |
| Population Exposed | 872.7K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-18T02:11:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.7656007f30d8691d4351a877a16aae7b |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Blue Earth, MN; Waseca, MN; Calhoun, IA; Hamilton, IA; Humboldt, IA; Kossuth, IA; Palo Alto, IA; Pocahontas, IA; Webster, IA; Wright, IA; Buena Vista, IA; Clay, IA; Dickinson, IA and 16 more areas |
| Headline | Severe Thunderstorm Warning issued May 17 at 9:11PM CDT until May 17 at 9:45PM CDT by NWS Twin Cities/Chanhassen MN |
| Expires | 2026-05-17T21:45:00-05:00 |
| SenderName | NWS Twin Cities/Chanhassen MN |
| HasExactCoords | true |
| MergedCount | 21 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.7656007f30d8691d4351a877a16aae7b016e497b.002.1","noaa_urn:oid:2.49.0.1.840.0.e52c4a2c482d7e25c61a5657ce2c376fcc21bda1.001.1","noaa_urn:oid:2.49.0.1.840.0.386b1ee7c64188026c9b647afadc5ec83c9d01be.002.1","noaa_urn:oid:2.49.0.1.840.0.c4876b21806a37360c57e3e78e4bca64484a7ff1.001.1","noaa_urn:oid:2.49.0.1.840.0.963b1a7b1e6ef6660a7b9c0646c33f4dd5240c51.001.1","noaa_urn:oid:2.49.0.1.840.0.818552ae93cbb790cbe3272d8a60a9050ee40936.001.1","noaa_urn:oid:2.49.0.1.840.0.f717ca15d5b2701b17fbf2c66f7bf20716a37076.001.1","noaa_urn:oid:2.49.0.1.840.0.ee8b2d5ff7a671d6f1708cd4d891d98d590254b6.001.1","noaa_urn:oid:2.49.0.1.840.0.f71815c04e40e804b602ba0b20230797df9adcfe.001.1","noaa_urn:oid:2.49.0.1.840.0.53644d6b79a6a658bebaaebe1049989fb5be2fc1.001.1","noaa_urn:oid:2.49.0.1.840.0.7744a48215a5b4eae6e280b1a0474ac59b67975a.001.1","noaa_urn:oid:2.49.0.1.840.0.3b5c4dd44ef0aa5fc827fc70ea6697a71450c85d.001.1","noaa_urn:oid:2.49.0.1.840.0.7bac2177a1f0a8deeb3ef669110faa08a5deb82a.001.1","noaa_urn:oid:2.49.0.1.840.0.2f5de5a821cc6417cef2bd1f5078ec155107a252.001.1","noaa_urn:oid:2.49.0.1.840.0.0b57270698534184d6658bc5bd37751daa08c5f2.001.1","noaa_urn:oid:2.49.0.1.840.0.4da3d534972971f36c9f9a5b5faa9ec893c8dfdb.001.1","noaa_urn:oid:2.49.0.1.840.0.df5de06e5d7f1392e5756c7b21f90036ac493f5f.001.1","noaa_urn:oid:2.49.0.1.840.0.5952180d5e0eb32d5e504ac3622494cb423c7e9a.001.1","noaa_urn:oid:2.49.0.1.840.0.42f6c8b2079558ae0b443c181835a16a482aa1c4.001.1","noaa_urn:oid:2.49.0.1.840.0.d67d916fab6f876e0e92f4288706f03fafa88802.001.1","noaa_urn:oid:2.49.0.1.840.0.03cea8898672ad9575e5e69b95d8b1df5e96a02b.001.1"] |
| Iem TypeSummary | G |
| Iem Magnitude | 59 |
| Iem Unit | MPH |
| Iem City | 4 WSW Murdock |
| Iem County | Cass |
| Iem State | NE |
| Iem Wfo | OAX |
| Iem Remark | Personal Weather Station. |
| Google News RssFeed | weather |
| Google News SourceName | Hays Post |
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.
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Calamity.live data shows a weather event with CalamityScore 48/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.