This alert expired on 10 August 2026 at 23:15 UTC. It is kept here as a record.
It is the 8th strongest of the 40 detections recorded within 20 km of this point since 2 June 2026. Another comparable one was recorded here earlier the same day. 12 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued August 10 at 6:28PM EDT until August 10 at 7:15PM EDT by NWS Charleston SC
An estimated 94,339 people live within 50 km of this point.
Nearby, since 2 June 2026
- July 10, 2026 · score 39 · 3.2 km
- August 28, 2026 · score 39 · 3.6 km
- August 29, 2026 · score 63 · 6.5 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 39 out of 100, at 89 % 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) | 39 / 100 |
| Our confidence | 89% |
| Coordinates | 32.2877, -80.4054 |
| Nearest City | Hilton Head (33 km) |
| Population Exposed | 94.3K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-10T22:28:00.000Z |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Coastal waters from Edisto Beach SC to Savannah GA out 20 NM; Waters from Edisto Beach SC to Savannah GA extending from 20 to 60 NM |
| Headline | Special Marine Warning issued August 10 at 6:28PM EDT until August 10 at 7:15PM EDT by NWS Charleston SC |
| Expires | 2026-08-10T19:15:00-04:00 |
| SenderName | NWS Charleston SC |
| HasExactCoords | true |
| Iem TypeSummary | M |
| Iem Magnitude | 48 |
| Iem Unit | mph |
| Iem City | 6 N Fripp Island |
| Iem County | AMZ362 |
| Iem State | SC |
| Iem Wfo | CHS |
| Iem Remark | The St. Helena site gusted to 42 kt. |
| MergedSources | [{"id":"iem_D_32.780_-80.730_1786390200000","source":"iem","severity":"low","severityValue":25,"timestamp":1786390200000,"latitude":32.78,"longitude":-80.73},{"id":"iem_M_32.410_-80.460_1786400100000","source":"iem","severity":"low","severityValue":25,"timestamp":1786400100000,"latitude":32.41,"longitude":-80.46}] |
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 39/100, near Hilton Head (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 191 scientific monitoring sources.