Right now
The most recent data we hold from NOAA arrived 2 hours 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 1 June 2026 at 00:00 UTC. It is kept here as a record.
It is the 13th strongest of the 30 detections recorded within 20 km of this point since 8 April 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 31 at 6:32PM CDT until May 31 at 7:00PM CDT by NWS Aberdeen SD
An estimated 28,102 people live within 50 km of this point.
Nearby, since 8 April 2026
- May 31, 2026 · score 40 · 3.7 km
- June 1, 2026 · score 40 · 11.7 km
How we know
Confirmed by 4 independent sources, including NOAA.
Our own score for this event is 34 out of 100, at 88 % 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) | 34 / 100 |
| Our confidence | 88% |
| Coordinates | 45.7213, -98.9740 |
| Nearest City | Aberdeen (48 km) |
| Population Exposed | 28.1K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-31T23:32:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.359875068209d96269922071b1721340 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | McPherson, SD |
| Headline | Severe Thunderstorm Warning issued May 31 at 6:32PM CDT until May 31 at 7:00PM CDT by NWS Aberdeen SD |
| Expires | 2026-05-31T19:00:00-05:00 |
| SenderName | NWS Aberdeen SD |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.359875068209d96269922071b1721340b9acc475.002.1","noaa_urn:oid:2.49.0.1.840.0.2c39066a370feb8c249923018c4c98b550079458.001.1"] |
| Iem TypeSummary | H |
| Iem Magnitude | 1 |
| Iem Unit | Inch |
| Iem City | 6 SE Roscoe |
| Iem County | Edmunds |
| Iem State | SD |
| Iem Wfo | ABR |
| Iem Remark | Mostly nickel to quarter size. |
| MergedSources | [{"id":"iem_H_45.410_-99.230_1780262880000","source":"iem","severity":"low","severityValue":25,"timestamp":1780262880000,"latitude":45.41,"longitude":-99.23},{"id":"iem_H_45.680_-98.960_1780269600000","source":"iem","severity":"low","severityValue":25,"timestamp":1780269600000,"latitude":45.68,"longitude":-98.96},{"id":"iem_H_45.400_-99.240_1780262700000","source":"iem","severity":"low","severityValue":25,"timestamp":1780262700000,"latitude":45.4,"longitude":-99.24}] |
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.
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