This alert expired on 11 July 2026 at 22:50 UTC. It is kept here as a record.
No stronger detection stands among the 19 recorded within 20 km of this point since 16 March 2026 — 9 others scored the same. Another comparable one was recorded here earlier the same day. 5 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued July 11 at 6:40PM EDT until July 11 at 6:45PM EDT by NWS Charleston SC
An estimated 213,926 people live within 50 km of this point.
Nearby, since 16 March 2026
- August 30, 2026 · score 43 · 1.0 km
- August 6, 2026 · score 43 · 19.2 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 | 32.4740, -79.6052 |
| Nearest City | Mount Pleasant (42 km) |
| Population Exposed | 213.9K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-11T22:40:00.000Z |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Charleston Harbor; 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; Waters from South Santee River SC to Edisto Beach SC extending from 20 to 60 NM; Waters from Edisto Beach SC to Savannah GA extending from 20 to 60 NM |
| Headline | Special Marine Warning issued July 11 at 6:40PM EDT until July 11 at 6:45PM EDT by NWS Charleston SC |
| Expires | 2026-07-11T18:50:00-04:00 |
| SenderName | NWS Charleston SC |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.5770e3a4349c0358e2075f4ea031904bd6275b0c.001.1","noaa_urn:oid:2.49.0.1.840.0.9cc1d601a3b4033f7513230ef8164f404712a85e.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.
Calamity.live data shows a weather event with CalamityScore 43/100, near Mount Pleasant (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 194 scientific monitoring sources.