Severe Weather near Greater Upper Marlboro
This alert expired on 8 August 2026 at 21:30 UTC. It is kept here as a record.
It is the 9th strongest of the 159 detections recorded within 20 km of this point since 16 March 2026. The last comparable one was on 6 August 2026. 12 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued August 8 at 4:04PM EDT until August 8 at 5:30PM EDT by NWS Baltimore MD/Washington DC
An estimated 3,130,832 people live within 50 km of this point.
Nearby, since 16 March 2026
- July 4, 2026 · score 52 · 3.8 km
- March 21, 2026 · score 52 · 3.8 km
- August 8, 2026 · score 52 · 4.8 km
How we know
Confirmed by 7 independent sources, including NOAA.
Our own score for this event is 52 out of 100, at 90 % 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 | 90% |
| Coordinates | 38.6773, -76.7234 |
| Nearest City | Greater Upper Marlboro (17 km) |
| Population Exposed | 3.1M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-08T20:04:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Special Marine Warning_noaa_urn:oid:2.49.0.1.840.0.867da38370f0de2d5870f25349e3d115 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Chesapeake Bay from Sandy Point to North Beach MD; Eastern Bay; Tidal Potomac from Indian Head to Cobb Island MD |
| Headline | Special Marine Warning issued August 8 at 4:04PM EDT until August 8 at 5:30PM EDT by NWS Baltimore MD/Washington DC |
| Expires | 2026-08-08T17:30:00-04:00 |
| SenderName | NWS Baltimore MD/Washington DC |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.867da38370f0de2d5870f25349e3d11524203589.001.1","noaa_urn:oid:2.49.0.1.840.0.ae14bf12118044a0755e493317cdfd8d5aaa7c3d.001.1"] |
| Iem TypeSummary | M |
| Iem Magnitude | 39 |
| Iem Unit | mph |
| Iem City | 2 ENE Brooklyn Park |
| Iem County | Baltimore City |
| Iem State | MD |
| Iem Wfo | LWX |
| Iem Remark | A wind gust of 34 knots (39 MPH) was measured by the Baltimore Tower mesonet (MSI05) adjacent to the tidal Patapsco River. |
| MergedSources | [{"id":"iem_M_39.220_-76.530_1786210200000","source":"iem","severity":"low","severityValue":25,"timestamp":1786210200000,"latitude":39.22,"longitude":-76.53},{"id":"iem_M_39.280_-76.610_1786209540000","source":"iem","severity":"low","severityValue":25,"timestamp":1786209540000,"latitude":39.28,"longitude":-76.61},{"id":"iem_M_39.220_-76.250_1786210740000","source":"iem","severity":"low","severityValue":25,"timestamp":1786210740000,"latitude":39.22,"longitude":-76.25},{"id":"iem_M_39.220_-76.530_1786209840000","source":"iem","severity":"low","severityValue":25,"timestamp":1786209840000,"latitude":39.22,"longitude":-76.53},{"id":"iem_M_39.200_-76.520_1786210200000","source":"iem","severity":"low","severityValue":25,"timestamp":1786210200000,"latitude":39.2,"longitude":-76.52},{"id":"iem_M_39.230_-76.580_1786210200000","source":"iem","severity":"low","severityValue":25,"timestamp":1786210200000,"latitude":39.23,"longitude":-76.58}] |
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 Greater Upper Marlboro?
Calamity.live data shows a weather event with CalamityScore 52/100, near Greater Upper Marlboro (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.