This alert expired on 4 July 2026 at 20:15 UTC. It is kept here as a record.
It is the 2nd strongest of the 81 detections recorded within 20 km of this point since 15 March 2026. Another comparable one was recorded here earlier the same day. 22 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued July 4 at 1:43PM MDT until July 4 at 2:15PM MDT by NWS Rapid City SD
Nearby, since 15 March 2026
- July 7, 2026 · score 22 · 11.7 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 22 out of 100, at 68 % 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) | 22 / 100 |
| Our confidence | 68% |
| Coordinates | 43.6315, -103.5847 |
| Nearest City | Rapid City (57 km) |
| Impact Tier | minor |
| Timestamp | 2026-07-04T19:43:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.7d0a2229632789613663b9b09a984335 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Custer, SD |
| Headline | Severe Thunderstorm Warning issued July 4 at 1:43PM MDT until July 4 at 2:15PM MDT by NWS Rapid City SD |
| Expires | 2026-07-04T14:15:00-06:00 |
| SenderName | NWS Rapid City SD |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.7d0a2229632789613663b9b09a9843352ea13baa.001.1","noaa_urn:oid:2.49.0.1.840.0.957a6e0f5cb4882e314bc49d5a1609356dea9806.001.1"] |
| Iem TypeSummary | H |
| Iem Magnitude | 2 |
| Iem Unit | inch |
| Iem City | 5 SSW Custer |
| Iem County | Custer |
| Iem State | SD |
| Iem Wfo | UNR |
| Iem Remark | mPING report |
| MergedSources | [{"id":"iem_H_43.700_-103.630_1783193520000","source":"iem","severity":"low","severityValue":25,"timestamp":1783193520000,"latitude":43.7,"longitude":-103.63},{"id":"iem_H_43.700_-103.630_1783194240000","source":"iem","severity":"low","severityValue":25,"timestamp":1783194240000,"latitude":43.7,"longitude":-103.63}] |
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.
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 188 scientific monitoring sources.