Right now
The most recent data we hold from NOAA arrived 3 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 20 June 2026 at 22:01 UTC. It is kept here as a record.
No stronger detection stands among the 16 recorded within 20 km of this point since 30 March 2026 — 3 others scored the same. The last comparable one was on 19 May 2026.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued June 20 at 3:51PM MDT until June 20 at 4:00PM MDT by NWS Cheyenne WY
Urban PEI: 60,285 within a heuristic 50 km radius; not unique people.
Nearby, since 30 March 2026
- August 10, 2026 · score 39 · 13.1 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 39 out of 100.
This is our versioned heuristic index, not source severity or a calibrated probability. Urban PEI does not count unique people.
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) | 39 / 100 |
| Legacy data-support index | 0.78/1 |
| Coordinates | 42.6758, -105.9092 |
| Nearest City | Casper (39 km) |
| Urban exposure index (PEI) | 60.3K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-06-20T21:51:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.5ce0d22c02637788e99611ffdeae4bf4 |
Physical priority index · v1. Heuristic priority, not calibrated probability, predictive accuracy or damage. The legacy data-support index combines assigned source support and field availability. Urban PEI is distance-weighted and does not count unique people; zero does not establish that nobody is present. Model cards.
Source and revision timeline
Source: noaa. Occurrence: 2026-06-20T21:51:00.000Z.
First archived: 2026-06-20T21:53:01.065Z. Material modification: not recorded.
Retained revisions are prospective; earlier versions may be unavailable. No revision entry does not prove that a record never changed.
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Goshen, WY; Laramie, WY; Platte, WY; Converse, WY; Johnson, WY; Natrona, WY and 4 more areas |
| Headline | Severe Thunderstorm Warning issued June 20 at 3:51PM MDT until June 20 at 4:00PM MDT by NWS Cheyenne WY |
| Expires | 2026-06-20T16:01:00-06:00 |
| SenderName | NWS Cheyenne WY |
| HasExactCoords | true |
| MergedCount | 7 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.5ce0d22c02637788e99611ffdeae4bf4e3a54d03.001.1","noaa_urn:oid:2.49.0.1.840.0.70711cba73a13b40afd39968e75fca49cb44ec5d.001.1","noaa_urn:oid:2.49.0.1.840.0.b555961dbdafebd73f620a698b3b37f646c8468d.001.1","noaa_urn:oid:2.49.0.1.840.0.55c6271a7c4a996f147c2e74f8d7f62be1b147d3.001.1","noaa_urn:oid:2.49.0.1.840.0.700754b697a6dd3f07e080fd072a27e0b717b268.001.1","noaa_urn:oid:2.49.0.1.840.0.4de188e271c8f57cab0885d2965689843b7eafc6.001.1","noaa_urn:oid:2.49.0.1.840.0.296efafbee08f5f0851a89516be743370ab71d5b.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.
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