This alert expired on 3 August 2026 at 23:00 UTC. It is kept here as a record.
It is the 13th strongest of the 39 detections recorded within 20 km of this point since 11 May 2026. 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 August 3 at 5:32PM EDT until August 3 at 7:00PM EDT by NWS Charleston SC
An estimated 94,339 people live within 50 km of this point.
Nearby, since 11 May 2026
- July 10, 2026 · score 39 · 0.7 km
- June 24, 2026 · score 43 · 1.1 km
- June 2, 2026 · score 43 · 5.2 km
How we know
Confirmed by 2 independent sources, including NOAA.
Our own score for this event is 39 out of 100, at 85 % 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 | 85% |
| Coordinates | 32.2500, -80.5256 |
| Nearest City | Hilton Head Island (21 km) |
| Population Exposed | 94.3K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-03T21:32:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.cfbd51df0511e054d50f12594d91051dd69db4a8.001.1 |
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 |
| Headline | Special Marine Warning issued August 3 at 5:32PM EDT until August 3 at 7:00PM EDT by NWS Charleston SC |
| Expires | 2026-08-03T19:00:00-04:00 |
| SenderName | NWS Charleston SC |
| HasExactCoords | true |
| Iem TypeSummary | M |
| Iem Magnitude | 46 |
| Iem Unit | mph |
| Iem City | 6 WSW Forest Beach |
| Iem County | AMZ362 |
| Iem State | SC |
| Iem Wfo | CHS |
| Iem Remark | Calibogue Sound Weatherflow sensor reported a 40 knot wind gust. |
| MergedSources | [{"id":"iem_M_32.110_-80.840_1785790380000","source":"iem","severity":"low","severityValue":25,"timestamp":1785790380000,"latitude":32.11,"longitude":-80.84}] |
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 Hilton Head Island?
Calamity.live data shows a weather event with CalamityScore 39/100, near Hilton Head Island (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.