Right now
The most recent data we hold from NOAA arrived 17 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 6 September 2026 at 03:30 UTC. It is kept here as a record.
No stronger detection stands among the 158 recorded within 20 km of this point since 5 May 2026 — 102 others scored the same. The last comparable one was on 5 September 2026.
What the source measured
NOAA reported: Flash Flood Warning issued September 5 at 6:30PM MDT until September 5 at 9:30PM MDT by NWS Cheyenne WY
How we know
3 recorded sources include NOAA; independence is not established by this count.
Our own score for this event is 28 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 v4. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | High |
| Calamity Score (ours) | 28 / 100 |
| Legacy data-support index | 0.70/1 |
| Coordinates | 42.0341, -102.9070 |
| Nearest City | Cheyenne (188 km) |
| Urban exposure index (PEI) | 0 within 50 km |
| Impact Tier | minor |
| Timestamp | 2026-09-06T00:30:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.3f08049b75ef6d10cdaeb006224fdf77186355f8.001.1 |
Physical priority index · v4 (historical). 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: 2026-09-06T00:30:00.000Z.
First archived: 2026-09-06T00:32:24.302Z. 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 | Flash Flood Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Morrill, NE; Box Butte, NE; Box Butte, NE; Dawes, NE |
| Headline | Flash Flood Warning issued September 5 at 6:30PM MDT until September 5 at 9:30PM MDT by NWS Cheyenne WY |
| Expires | 2026-09-05T21:30:00-06:00 |
| SenderName | NWS Cheyenne WY |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.3f08049b75ef6d10cdaeb006224fdf77186355f8.001.1","noaa_urn:oid:2.49.0.1.840.0.6144d6b13bfb2b63b9aaeeb12a9e57062b45329e.001.1","noaa_urn:oid:2.49.0.1.840.0.876998c3c1746d9e2b963562dc9a436a12cef8b6.001.1"] |
| Spc ReportType | hail |
| Spc Speed | 125 |
| Spc Location | 3.5 E Minatare |
| Spc County | Scotts Bluff |
| Spc State | NE |
| Spc Comments | Trained spotter reported half dollar sized hail falling east of Minatare. (CYS) |
| Iem TypeSummary | F |
| Iem City | Alliance |
| Iem County | Box Butte |
| Iem State | NE |
Safety Information
During flooding: never walk, swim, or drive through floodwaters. Six inches of moving water can knock you down, and one foot of water can sweep away a vehicle. Move to higher ground if waters rise. After flooding, avoid contact with floodwater which may contain sewage, chemicals, or debris. Follow local emergency service guidance.
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.
Review the area, threshold and delivery channel in your account.
Want to know when something happens in this area?