This alert expired on 11 March 2026 at 05:00 UTC. It is kept here as a record.
It is the 7th strongest of the 242 detections recorded within 20 km of this point since 10 March 2026.
What the source measured
NOAA reported: Tornado Watch issued March 10 at 5:58PM CDT until March 11 at 12:00AM CDT by NWS Des Moines IA
An estimated 181,553 people live within 50 km of this point.
Nearby, since 10 March 2026
- September 2, 2026 · score 37 · 0.0 km
- September 1, 2026 · score 37 · 0.0 km
- August 13, 2026 · score 43 · 0.0 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 55 out of 100, at 78 % 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 | High |
| Calamity Score (ours) | 55 / 100 |
| Our confidence | 78% |
| Coordinates | 42.0000, -93.2000 |
| Nearest City | Marshalltown (25 km) |
| Population Exposed | 181.6K within 50 km |
| Impact Tier | severe |
| Timestamp | 2026-03-10T23:00:00.000Z |
| Source | https://api.weather.gov/alerts/urn-oid-2_49_0_1_840_0_f095193c8ba630d25af5c1db9407b102df5d5660_001_1 |
Score Breakdown
Technical Details
| Event | Tornado Watch |
| Urgency | Future |
| Certainty | Possible |
| AreaDesc | Davis, IA |
| Headline | Tornado Watch issued March 10 at 5:58PM CDT until March 11 at 12:00AM CDT by NWS Des Moines IA |
| Expires | 2026-03-11T00:00:00-05:00 |
| SenderName | NWS Des Moines IA |
| HasExactCoords | false |
Safety Information
If a tornado warning is issued: go to a basement or an interior room on the lowest floor, away from windows. A vehicle and a mobile home are not shelter. Cover your head and neck. Wait for the official all-clear before going outside, and watch for downed power lines and gas leaks afterwards.
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 55/100, near Marshalltown (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.