Right now
The most recent data we hold from NOAA arrived 63 minutes ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
11 other detections within 20 km in the last 24 hours, the nearest 8 km from here.
This alert expired on 31 July 2026 at 23:48 UTC. It is kept here as a record.
No stronger detection stands among the 76 recorded within 20 km of this point since 15 March 2026 — 38 others scored the same. Another comparable one was recorded here earlier the same day. 6 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued July 31 at 5:38PM MDT until July 31 at 5:45PM MDT by NWS Rapid City SD
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 22 out of 100, at 70 % 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) | 22 / 100 |
| Our confidence | 70% |
| Coordinates | 43.2483, -103.5533 |
| Nearest City | Rapid City (96 km) |
| Impact Tier | minor |
| Timestamp | 2026-07-31T23:38:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.f56543538cd93c4524cf3cc56d98939bef5975db.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Fall River, SD |
| Headline | Severe Thunderstorm Warning issued July 31 at 5:38PM MDT until July 31 at 5:45PM MDT by NWS Rapid City SD |
| Expires | 2026-07-31T17:48:00-06:00 |
| SenderName | NWS Rapid City SD |
| HasExactCoords | true |
| Iem TypeSummary | H |
| Iem Magnitude | 1 |
| Iem Unit | inch |
| Iem City | 2 SSW Custer |
| Iem County | Custer |
| Iem State | SD |
| Iem Wfo | UNR |
| MergedSources | [{"id":"iem_G_43.430_-103.690_1785538980000","source":"iem","severity":"low","severityValue":25,"timestamp":1785538980000,"latitude":43.43,"longitude":-103.69},{"id":"iem_H_43.740_-103.620_1785536700000","source":"iem","severity":"low","severityValue":25,"timestamp":1785536700000,"latitude":43.74,"longitude":-103.62}] |
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?
Calamity.live data shows a weather event with CalamityScore 22/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.