This alert expired on 19 May 2026 at 23:00 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. The last comparable one was on 14 May 2026. One more was recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued May 19 at 5:31PM EDT until May 19 at 7:00PM 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
- March 16, 2026 · score 52 · 0.3 km
- June 12, 2026 · score 52 · 1.4 km
- July 9, 2026 · score 52 · 1.5 km
How we know
Confirmed by 2 independent sources, including NOAA.
Our own score for this event is 52 out of 100, at 86 % 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 | 86% |
| Coordinates | 38.6550, -77.1672 |
| Nearest City | Lorton (7 km) |
| Population Exposed | 3.8M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-19T21:31:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.7b770ddb3b4240e889fadb02f2d045e756c42bb4.001.1 |
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 May 19 at 5:31PM EDT until May 19 at 7:00PM EDT by NWS Baltimore MD/Washington DC |
| Expires | 2026-05-19T19:00:00-04:00 |
| SenderName | NWS Baltimore MD/Washington DC |
| HasExactCoords | true |
| Google News RssFeed | weather |
| Google News SourceName | AOL.com |
| MergedSources | [{"id":"gnews_weather_494225_179","source":"google_news","severity":"medium","severityValue":40,"timestamp":1779211847000,"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.