This alert expired on 9 August 2026 at 15:30 UTC. It is kept here as a record.
It is the 4th strongest of the 27 detections recorded within 20 km of this point since 13 April 2026. The last comparable one was on 1 August 2026. 5 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued August 9 at 9:45AM CDT until August 9 at 10:30AM CDT by NWS Milwaukee/Sullivan WI
An estimated 348,213 people live within 50 km of this point.
Nearby, since 13 April 2026
- June 6, 2026 · score 67 · 7.9 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 43 out of 100, at 91 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Event Data
| Type | Severe weather |
| Severity | medium |
| Calamity Score (ours) | 43 / 100 |
| Our confidence | 91% |
| Coordinates | 43.4261, -89.2752 |
| Nearest City | Sun Prairie (28 km) |
| Population Exposed | 348.2K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-09T14:45:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.72f31989268bad5d39f6037f841d2db6 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Columbia, WI; Dane, WI; Columbia, WI; Green Lake, WI |
| Headline | Severe Thunderstorm Warning issued August 9 at 9:45AM CDT until August 9 at 10:30AM CDT by NWS Milwaukee/Sullivan WI |
| Expires | 2026-08-09T10:30:00-05:00 |
| SenderName | NWS Milwaukee/Sullivan WI |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.72f31989268bad5d39f6037f841d2db6979c562a.001.1","noaa_urn:oid:2.49.0.1.840.0.497262ee71de5953176816cededf5cc0bac467e0.001.1"] |
| Iem TypeSummary | G |
| Iem Magnitude | 50 |
| Iem Unit | MPH |
| Iem City | 1 S Kingston |
| Iem County | Green Lake |
| Iem State | WI |
| Iem Wfo | MKX |
| MergedSources | [{"id":"iem_H_43.660_-89.210_1786285680000","source":"iem","severity":"low","severityValue":25,"timestamp":1786285680000,"latitude":43.66,"longitude":-89.21},{"id":"iem_G_43.680_-89.130_1786286160000","source":"iem","severity":"low","severityValue":25,"timestamp":1786286160000,"latitude":43.68,"longitude":-89.13}] |
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 10 February 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 Sun Prairie?
Calamity.live data shows a weather event with CalamityScore 43/100, near Sun Prairie (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.