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.
2 other detections within 20 km in the last 24 hours, the nearest <1 km from here.
This alert expired on 9 July 2026 at 05:00 UTC. It is kept here as a record.
It is the 68th strongest of the 248 detections recorded within 20 km of this point since 10 March 2026. The last comparable one was on 8 July 2026. 54 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Watch issued July 8 at 7:21PM CDT until July 9 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 43 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) | 43 / 100 |
| Legacy data-support index | 0.80/1 |
| Coordinates | 42.0000, -93.2000 |
| Nearest City | Marshalltown (25 km) |
| Urban exposure index (PEI) | 181.6K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-09T00:21:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Watch_noaa_urn:oid:2.49.0.1.840.0.ced0316b9fbd14c062b4a95b62dfd54d |
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: 2026-07-09T00:21:00.000Z.
First archived: 2026-07-09T00:48:16.144Z. 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 Watch |
| Urgency | Future |
| Certainty | Possible |
| AreaDesc | Harrison, IA; Mills, IA; Monona, IA; Pottawattamie, IA; Shelby, IA; Burt, NE; Butler, NE; Cass, NE; Colfax, NE; Cuming, NE; Dodge, NE; Douglas, NE; Gage, NE; Jefferson, NE; Lancaster, NE; Otoe, NE; Platte, NE; Saline, NE; Sarpy, NE; Saunders, NE; Seward, NE; Washington, NE; Ida, IA; Allamakee, IA; Chickasaw, IA; Clayton, IA; Fayette, IA; Floyd, IA; Howard, IA; Mitchell, IA; Winneshiek, IA; Crawford, WI; Grant, WI; Richland, WI and 1 more areas |
| Headline | Severe Thunderstorm Watch issued July 8 at 7:21PM CDT until July 9 at 12:00AM CDT by NWS Omaha/Valley NE |
| Expires | 2026-07-09T00:00:00-05:00 |
| SenderName | NWS Omaha/Valley NE |
| HasExactCoords | false |
| MergedCount | 4 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.ced0316b9fbd14c062b4a95b62dfd54d0e58c51e.002.1","noaa_urn:oid:2.49.0.1.840.0.e9749f06e33e7f94763ccc9dac048f263342bcca.002.1","noaa_urn:oid:2.49.0.1.840.0.9ec7d5b75ceb6c2bf419bb1869e6ef6b0757dbc8.002.1","noaa_urn:oid:2.49.0.1.840.0.95a06dd1595947e59cb1f0b1f15d230c035507d5.001.1"] |
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.
Review the area, threshold and delivery channel in your account.
Want to know when something happens near Marshalltown?