This alert expired on 12 August 2026 at 21:15 UTC. It is kept here as a record.
No stronger detection stands among the 29 recorded within 20 km of this point since 8 March 2026 — 17 others scored the same. The last comparable one was on 4 August 2026. 2 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued August 12 at 4:14PM EDT until August 12 at 5:15PM EDT by NWS Jacksonville FL
An estimated 1,106,284 people live within 50 km of this point.
Nearby, since 8 March 2026
- June 15, 2026 · score 52 · 4.0 km
- July 15, 2026 · score 52 · 6.8 km
- June 17, 2026 · score 46 · 9.1 km
How we know
Confirmed by 8 independent sources, including NOAA.
Our own score for this event is 52 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) | 52 / 100 |
| Our confidence | 90% |
| Coordinates | 30.4279, -81.1660 |
| Nearest City | Jacksonville Beach (26 km) |
| Population Exposed | 1.1M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-12T20:14:00.000Z |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Coastal waters from Fernandina Beach to St. Augustine FL out 20 NM; Coastal waters from St. Augustine to Flagler Beach FL out 20 NM; Waters from Fernandina Beach to St. Augustine FL from 20 to 60 NM; Waters from St. Augustine to Flagler Beach FL from 20 to 60 NM; Coastal waters from Altamaha Sound to Fernandina Beach FL out 20 NM; Coastal waters from Fernandina Beach to St. Augustine FL out 20 NM; Waters from Altamaha Sound GA to Fernandina Beach FL from 20 to 60 NM; Waters from Fernandina Beach to St. Augustine FL from 20 to 60 NM |
| Headline | Special Marine Warning issued August 12 at 4:14PM EDT until August 12 at 5:15PM EDT by NWS Jacksonville FL |
| Expires | 2026-08-12T17:15:00-04:00 |
| SenderName | NWS Jacksonville FL |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.88d3856c21c3377dadb892866d98719fe53786d0.001.1","noaa_urn:oid:2.49.0.1.840.0.7b5642cd990631565107ff7ae18406c0b942e506.001.1"] |
| Iem TypeSummary | G |
| Iem Magnitude | 40 |
| Iem Unit | MPH |
| Iem City | 1 N Bakersville |
| Iem County | St. Johns |
| Iem State | FL |
| Iem Wfo | JAX |
| Iem Remark | Mesonet station GW6650 SAINT AUGUSTINE measured a gust of 40 mph. |
| MergedSources | [{"id":"iem_G_30.390_-81.480_1786556040000","source":"iem","severity":"low","severityValue":25,"timestamp":1786556040000,"latitude":30.39,"longitude":-81.48},{"id":"iem_G_30.390_-81.500_1786556400000","source":"iem","severity":"low","severityValue":25,"timestamp":1786556400000,"latitude":30.39,"longitude":-81.5},{"id":"iem_G_30.500_-81.680_1786559460000","source":"iem","severity":"low","severityValue":25,"timestamp":1786559460000,"latitude":30.5,"longitude":-81.68},{"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},{"id":"iem_M_29.890_-81.310_1786564800000","source":"iem","severity":"low","severityValue":25,"timestamp":1786564800000,"latitude":29.89,"longitude":-81.31},{"id":"iem_G_29.920_-81.490_1786564200000","source":"iem","severity":"low","severityValue":25,"timestamp":1786564200000,"latitude":29.92,"longitude":-81.49}] |
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.
Calamity.live data shows a weather event with CalamityScore 52/100, near Jacksonville Beach (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 194 scientific monitoring sources.