Calamity
MediumSevere WeatherCalamity Score: 16

Severe Weather in United States

Fall RiverUnited StatesNOAA

Right now

The most recent data we hold from NOAA arrived 4 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 30 May 2026 at 21:15 UTC. It is kept here as a record.

It is the 11th strongest of the 71 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 30 at 2:51PM MDT until May 30 at 3:15PM MDT by NWS Cheyenne WY

How we know

One source: NOAA. Not yet confirmed by a second, independent source.

Our own score for this event is 16 out of 100, at 60 % 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

TypeSevere Weather
SeverityMedium
Calamity Score (ours)16 / 100
Our confidence60%
Coordinates43.3750, -103.9562
Nearest CityRapid City (98 km)
Impact Tierminor
Timestamp2026-05-30T20:51:00.000Z
Sourcehttps://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.725941610a14e3cb61326f80c7124a93

Score Breakdown

35
intensity
0
population
0
cascading
18
historical

Technical Details

EventSevere Thunderstorm Warning
UrgencyImmediate
CertaintyObserved
AreaDescNiobrara, WY; Dawes, NE; Converse, WY; Goshen, WY; Niobrara, WY; Platte, WY and 2 more areas
HeadlineSevere Thunderstorm Warning issued May 30 at 2:51PM MDT until May 30 at 3:15PM MDT by NWS Cheyenne WY
Expires2026-05-30T15:15:00-06:00
SenderNameNWS Cheyenne WY
HasExactCoordstrue
MergedCount5
MergedIds["noaa_urn:oid:2.49.0.1.840.0.725941610a14e3cb61326f80c7124a93c5c38435.001.1","noaa_urn:oid:2.49.0.1.840.0.c8b6ef9d4f71fb934912ce9d5a066369abd12774.001.1","noaa_urn:oid:2.49.0.1.840.0.07e674ae8e10e1239be8ee0b3d515540cfa4f654.001.1","noaa_urn:oid:2.49.0.1.840.0.35147cb45ca6619fa716ef25461cfefef286e909.001.1","noaa_urn:oid:2.49.0.1.840.0.ead0948743cf941a40f2a775e65b0370f41777cf.001.1"]

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 in this area?

Share:XLinkedIn