Right now
The most recent data we hold from NOAA arrived 69 minutes ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
This alert expired on 21 July 2026 at 02:00 UTC. It is kept here as a record.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued July 20 at 8:21PM CDT until July 20 at 9:00PM CDT by NWS Des Moines IA
Urban PEI: 24,624 within a heuristic 50 km radius; not unique people.
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 28 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) | 28 / 100 |
| Legacy data-support index | 0.80/1 |
| Coordinates | 40.9435, -92.4129 |
| Nearest City | Ottumwa (9 km) |
| Urban exposure index (PEI) | 24.6K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-21T01:21:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.76dac2bf11e0af701b3c572b18982e62 |
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: 2026-07-21T01:21:00.000Z.
First archived: 2026-07-21T01:24:41.736Z. 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 Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Lucas, IA; Mahaska, IA; Marion, IA; Monroe, IA; Hancock, IL; McDonough, IL; Lee, IA; Marion, IA |
| Headline | Severe Thunderstorm Warning issued July 20 at 8:21PM CDT until July 20 at 9:00PM CDT by NWS Des Moines IA |
| Expires | 2026-07-20T21:00:00-05:00 |
| SenderName | NWS Des Moines IA |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.76dac2bf11e0af701b3c572b18982e626a5dbf8e.001.1","noaa_urn:oid:2.49.0.1.840.0.0b08eb7fa919937c924a6b66e658419982b61bea.001.1","noaa_urn:oid:2.49.0.1.840.0.7813c65167abe9802cde105b23ee4f7adf02fc27.002.1"] |
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.
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