This alert expired on 12 August 2026 at 19:45 UTC. It is kept here as a record.
It is the 4th strongest of the 77 detections recorded within 20 km of this point since 15 March 2026. Another comparable one was recorded here earlier the same day. 4 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued August 12 at 3:38PM EDT until August 12 at 3:45PM EDT by NWS Jacksonville FL
An estimated 288,807 people live within 50 km of this point.
Nearby, since 15 March 2026
- June 18, 2026 · score 43 · 8.0 km
- June 13, 2026 · score 37 · 8.5 km
- July 20, 2026 · score 43 · 9.1 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 43 out of 100, at 90 % 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 | 90% |
| Coordinates | 29.8426, -81.3805 |
| Nearest City | St. Johns (31 km) |
| Population Exposed | 288.8K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-12T19:38:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.91a38de2234303f4690870cfe9469241868b1b18.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Clay, FL; Putnam, FL; St. Johns, FL |
| Headline | Severe Thunderstorm Warning issued August 12 at 3:38PM EDT until August 12 at 3:45PM EDT by NWS Jacksonville FL |
| Expires | 2026-08-12T15:45:00-04:00 |
| SenderName | NWS Jacksonville FL |
| HasExactCoords | true |
| Iem TypeSummary | G |
| Iem Magnitude | 44 |
| Iem Unit | MPH |
| Iem City | 4 NE Orange Park |
| Iem County | Duval |
| Iem State | FL |
| Iem Wfo | JAX |
| Iem Remark | AWOS station KNIP Jacksonville NAS measured a peak gust of 44 mph. |
| MergedSources | [{"id":"iem_G_29.990_-81.680_1786562100000","source":"iem","severity":"low","severityValue":25,"timestamp":1786562100000,"latitude":29.99,"longitude":-81.68},{"id":"iem_G_30.220_-81.670_1786560780000","source":"iem","severity":"low","severityValue":25,"timestamp":1786560780000,"latitude":30.22,"longitude":-81.67}] |
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 St. Johns?
Calamity.live data shows a weather event with CalamityScore 43/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 187 scientific monitoring sources.