Right now
The most recent data we hold from NOAA arrived 3 minutes ago, and this point is in it.
One other detection within 20 km in the last 24 hours, <1 km from here.
This alert is in force until 15 September 2026, 05:00 UTC.
It is the 7th strongest of the 248 detections recorded within 20 km of this point since 10 March 2026. The last comparable one was on 6 September 2026. 9 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Tornado Watch issued September 14 at 4:51PM CDT until September 15 at 12:00AM CDT by NWS Omaha/Valley NE
Urban PEI: 181,553 within a heuristic 50 km radius; not unique people.
Nearby, since 10 March 2026
- September 14, 2026 · score 55 · 0.0 km
- September 6, 2026 · score 37 · 0.0 km
- September 2, 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 55 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 v5. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | Medium |
| Calamity Score (ours) | 55 / 100 |
| Legacy data-support index | 0.79/1 |
| Coordinates | 42.0000, -93.2000 |
| Nearest City | Marshalltown (25 km) |
| Urban exposure index (PEI) | 181.6K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-09-14T21:51:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.a08783f6ae0dc6debf71ef246ce5836bb0cbccb1.001.1 |
Physical priority index · v5. 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: 2026-09-14T21:51:00.000Z.
First archived: 2026-09-14T21:54:08.454Z. 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 | Tornado Watch |
| Urgency | Future |
| Certainty | Possible |
| AreaDesc | Fremont, IA; Harrison, IA; Mills, IA; Montgomery, IA; Page, IA; Pottawattamie, IA; Shelby, IA; Butler, NE; Cass, NE; Dodge, NE; Douglas, NE; Gage, NE; Jefferson, NE; Johnson, NE; Lancaster, NE; Nemaha, NE; Otoe, NE; Pawnee, NE; Saline, NE; Sarpy, NE; Saunders, NE; Seward, NE; Washington, NE |
| Headline | Tornado Watch issued September 14 at 4:51PM CDT until September 15 at 12:00AM CDT by NWS Omaha/Valley NE |
| Expires | 2026-09-15T00:00:00-05:00 |
| SenderName | NWS Omaha/Valley NE |
| 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.
Review the area, threshold and delivery channel in your account.
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