This alert expired on 16 March 2026 at 16:45 UTC. It is kept here as a record.
It is the 7th strongest of the 162 detections recorded within 20 km of this point since 12 March 2026. Another comparable one was recorded here earlier the same day. 2 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued March 16 at 11:42AM EDT until March 16 at 12:45PM EDT by NWS Baltimore MD/Washington DC
An estimated 3,755,066 people live within 50 km of this point.
Nearby, since 12 March 2026
- May 19, 2026 · score 52 · 0.3 km
- July 9, 2026 · score 52 · 1.3 km
- June 11, 2026 · score 46 · 1.4 km
How we know
Confirmed by 4 independent sources, including NOAA.
Our own score for this event is 52 out of 100, at 88 % 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 | 88% |
| Coordinates | 38.6522, -77.1672 |
| Nearest City | Lorton (8 km) |
| Population Exposed | 3.8M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-03-16T15:42:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.7c1bf07cd1e840dc56f1695e6f60f299bbee45e7.001.1 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Tidal Potomac from Key Bridge to Indian Head MD; Tidal Potomac from Indian Head to Cobb Island MD |
| Headline | Special Marine Warning issued March 16 at 11:42AM EDT until March 16 at 12:45PM EDT by NWS Baltimore MD/Washington DC |
| Expires | 2026-03-16T12:45:00-04:00 |
| SenderName | NWS Baltimore MD/Washington DC |
| HasExactCoords | true |
| Google News RssFeed | weather |
| Google News SourceName | The Washington Post |
| MergedSources | [{"id":"gnews_weather_492688_122","source":"google_news","severity":"medium","severityValue":40,"timestamp":1773677618000,"latitude":38.9,"longitude":-77.04},{"id":"gnews_weather_492686_125","source":"google_news","severity":"medium","severityValue":40,"timestamp":1773672660000,"latitude":38.9,"longitude":-77.04},{"id":"gnews_weather_492687_136","source":"google_news","severity":"medium","severityValue":40,"timestamp":1773673599000,"latitude":38.9,"longitude":-77.04}] |
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 Lorton (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.