Right now
The most recent data we hold from NOAA arrived 22 minutes ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
2 other detections within 20 km in the last 24 hours, the nearest <1 km from here.
This alert expired on 7 September 2026 at 03:00 UTC. It is kept here as a record.
It is the 208th strongest of the 246 detections recorded within 20 km of this point since 10 March 2026. The last comparable one was on 2 September 2026.
What the source measured
NOAA reported: Severe Thunderstorm Watch issued September 6 at 4:45PM CDT until September 6 at 10:00PM CDT by NWS Des Moines IA
An estimated 181,553 people live within 50 km of this point.
Nearby, since 10 March 2026
- September 6, 2026 · score 37 · 0.0 km
- September 2, 2026 · score 37 · 0.0 km
- September 1, 2026 · score 37 · 0.0 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 37 out of 100, at 80 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
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 | Medium |
| Calamity Score (ours) | 37 / 100 |
| Our confidence | 80% |
| Coordinates | 42.0000, -93.2000 |
| Nearest City | Marshalltown (25 km) |
| Population Exposed | 181.6K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-09-06T21:45:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.c13c74a67de7a21981b5fc90ae77d386898752dd.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Watch |
| Urgency | Future |
| Certainty | Possible |
| AreaDesc | Adair, IA; Adams, IA; Audubon, IA; Boone, IA; Cass, IA; Clarke, IA; Dallas, IA; Decatur, IA; Greene, IA; Guthrie, IA; Madison, IA; Polk, IA; Ringgold, IA; Taylor, IA; Union, IA; Warren, IA; Fremont, IA; Mills, IA; Montgomery, IA; Page, IA; Pottawattamie, IA; Shelby, IA |
| Headline | Severe Thunderstorm Watch issued September 6 at 4:45PM CDT until September 6 at 10:00PM CDT by NWS Des Moines IA |
| Expires | 2026-09-06T22:00:00-05:00 |
| SenderName | NWS Des Moines IA |
| HasExactCoords | false |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.c13c74a67de7a21981b5fc90ae77d386898752dd.001.1","noaa_urn:oid:2.49.0.1.840.0.7f2fc37cbac0cf16c747ff9ec96d442cd67ecf53.001.1"] |
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.
Want to know when something happens near Marshalltown?
Calamity.live data shows a weather event with CalamityScore 37/100, near Marshalltown (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.