This alert expired on 11 August 2026 at 23:30 UTC. It is kept here as a record.
No stronger detection stands among the 56 recorded within 20 km of this point since 16 March 2026 — 19 others scored the same. The last comparable one was on 8 August 2026. 4 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued August 11 at 5:24PM EDT until August 11 at 7:30PM EDT by NWS Charleston SC
An estimated 280,390 people live within 50 km of this point.
Nearby, since 16 March 2026
- July 12, 2026 · score 43 · 12.0 km
- July 7, 2026 · score 37 · 13.0 km
- June 18, 2026 · score 43 · 13.1 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, at 80 % 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 | 80% |
| Coordinates | 31.9404, -80.8111 |
| Nearest City | Wilmington Island (16 km) |
| Population Exposed | 280.4K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-11T21:24:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Special Marine Warning_noaa_urn:oid:2.49.0.1.840.0.5993091db27f8890624eb9b79d4a7982 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Coastal waters from Savannah GA to Altamaha Sound GA out 20 nm, including Grays Reef National Marine Sanctuary; Coastal waters from South Santee River to Edisto Beach SC out 20 NM; Coastal waters from Edisto Beach SC to Savannah GA out 20 NM |
| Headline | Special Marine Warning issued August 11 at 5:24PM EDT until August 11 at 7:30PM EDT by NWS Charleston SC |
| Expires | 2026-08-11T19:30:00-04:00 |
| SenderName | NWS Charleston SC |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.5993091db27f8890624eb9b79d4a798215775ad0.001.1","noaa_urn:oid:2.49.0.1.840.0.a78ca805885a928307ac118eab76b7c3781bc077.001.1"] |
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 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 Wilmington Island?
Calamity.live data shows a weather event with CalamityScore 43/100, near Wilmington Island (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.