This alert expired on 6 July 2026 at 02:00 UTC. It is kept here as a record.
It is the 16th strongest of the 198 detections recorded within 20 km of this point since 11 March 2026. Another comparable one was recorded here earlier the same day. 21 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued July 5 at 9:14PM EDT until July 5 at 10:00PM EDT by NWS Baltimore MD/Washington DC
An estimated 4,788,930 people live within 50 km of this point.
Nearby, since 11 March 2026
- July 28, 2026 · score 52 · 2.4 km
- July 9, 2026 · score 52 · 3.0 km
- June 11, 2026 · score 46 · 5.1 km
How we know
Confirmed by 13 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 | 38.9145, -76.6918 |
| Nearest City | Bowie (4 km) |
| Population Exposed | 4.8M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-06T01:14:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Special Marine Warning_noaa_urn:oid:2.49.0.1.840.0.85357537e78f5f4f121521697f618c63 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Chesapeake Bay north of Pooles Island MD; Chesapeake Bay from Pooles Island to Sandy Point MD; Chesapeake Bay from Sandy Point to North Beach MD; Patapsco River including Baltimore Harbor; Chester River to Queenstown MD; Eastern Bay; Choptank River to Cambridge MD and the Little Choptank River; Tidal Potomac from Key Bridge to Indian Head MD; Tidal Potomac from Indian Head to Cobb Island MD |
| Headline | Special Marine Warning issued July 5 at 9:14PM EDT until July 5 at 10:00PM EDT by NWS Baltimore MD/Washington DC |
| Expires | 2026-07-05T22:00:00-04:00 |
| SenderName | NWS Baltimore MD/Washington DC |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.85357537e78f5f4f121521697f618c6370d6a6a2.001.1","noaa_urn:oid:2.49.0.1.840.0.f0755f5b2d79aa799a9288e6745ab89a363b3a7b.001.1"] |
| Iem TypeSummary | E |
| Iem City | 3 E Laytonsville |
| Iem County | Montgomery |
| Iem State | MD |
| Iem Wfo | LWX |
| Iem Remark | Montgomery County stream gauge reached minor flood stage along the Hawlings River at 22000 Zion Road. |
| MergedSources | [{"id":"iem_D_39.150_-77.050_1783294020000","source":"iem","severity":"low","severityValue":25,"timestamp":1783294020000,"latitude":39.15,"longitude":-77.05},{"id":"iem_D_39.160_-77.050_1783291380000","source":"iem","severity":"low","severityValue":25,"timestamp":1783291380000,"latitude":39.16,"longitude":-77.05},{"id":"iem_D_39.230_-77.120_1783290960000","source":"iem","severity":"low","severityValue":25,"timestamp":1783290960000,"latitude":39.23,"longitude":-77.12},{"id":"iem_D_38.970_-77.340_1783294500000","source":"iem","severity":"low","severityValue":25,"timestamp":1783294500000,"latitude":38.97,"longitude":-77.34},{"id":"iem_D_38.980_-77.380_1783294680000","source":"iem","severity":"low","severityValue":25,"timestamp":1783294680000,"latitude":38.98,"longitude":-77.38},{"id":"iem_G_39.180_-77.100_1783292760000","source":"iem","severity":"low","severityValue":25,"timestamp":1783292760000,"latitude":39.18,"longitude":-77.1},{"id":"iem_D_39.220_-77.060_1783291560000","source":"iem","severity":"low","severityValue":25,"timestamp":1783291560000,"latitude":39.22,"longitude":-77.06},{"id":"iem_D_39.170_-77.060_1783293660000","source":"iem","severity":"low","severityValue":25,"timestamp":1783293660000,"latitude":39.17,"longitude":-77.06},{"id":"iem_E_39.190_-77.040_1783297080000","source":"iem","severity":"low","severityValue":25,"timestamp":1783297080000,"latitude":39.19,"longitude":-77.04},{"id":"iem_D_38.960_-77.350_1783294500000","source":"iem","severity":"low","severityValue":25,"timestamp":1783294500000,"latitude":38.96,"longitude":-77.35},{"id":"iem_F_39.210_-77.090_1783297980000","source":"iem","severity":"low","severityValue":25,"timestamp":1783297980000,"latitude":39.21,"longitude":-77.09},{"id":"iem_E_39.210_-77.090_1783298220000","source":"iem","severity":"low","severityValue":25,"timestamp":1783298220000,"latitude":39.21,"longitude":-77.09}] |
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 Bowie?
Calamity.live data shows a weather event with CalamityScore 52/100, near Bowie (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.