Right now
The most recent data we hold from NOAA arrived 42 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 2 July 2026 at 07:00 UTC. It is kept here as a record.
It is the 74th strongest of the 254 detections recorded within 20 km of this point since 10 March 2026. The last comparable one was on 1 July 2026. 15 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Watch issued July 1 at 7:38PM CDT until July 2 at 2:00AM CDT by NWS Sioux Falls SD
Urban PEI: 181,553 within a heuristic 50 km radius; not unique people.
Nearby, since 10 March 2026
- September 15, 2026 · score 55 · 0.0 km
- September 14, 2026 · score 55 · 0.0 km
- September 6, 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 | 0.81/1 |
| Coordinates | 42.0000, -93.2000 |
| Nearest City | Marshalltown (25 km) |
| Urban exposure index (PEI) | 181.6K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-02T00:38:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.ab6b0f7f8359621370a11a3edf0d5a48a32eb041.001.1 |
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: 2026-07-02T00:38:00.000Z.
First archived: 2026-07-02T06:49:52.126Z. 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 | Buena Vista, IA; Cherokee, IA; Clay, IA; Dickinson, IA; Ida, IA; Lyon, IA; O'Brien, IA; Osceola, IA; Plymouth, IA; Sioux, IA; Woodbury, IA; Cottonwood, MN; Jackson, MN; Nobles, MN; Dakota, NE; Dixon, NE; Clay, SD; Union, SD |
| Headline | Severe Thunderstorm Watch issued July 1 at 7:38PM CDT until July 2 at 2:00AM CDT by NWS Sioux Falls SD |
| Expires | 2026-07-02T02:00:00-05:00 |
| SenderName | NWS Sioux Falls SD |
| HasExactCoords | false |
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.
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