Right now
The most recent data we hold from NOAA arrived 14 minutes ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
Nothing else has been detected within 20 km in the last 24 hours.
This alert expired on 4 September 2026 at 06:45 UTC. It is kept here as a record.
No stronger detection stands among the 10 recorded within 20 km of this point since 17 March 2026 — 2 others scored the same. Another comparable one was recorded here earlier the same day.
What the source measured
NOAA reported: Special Marine Warning issued September 4 at 1:42AM EDT until September 4 at 2:45AM EDT by NWS Baltimore MD/Washington DC
Urban PEI: 32,899 within a heuristic 50 km radius; not unique people.
Nearby, since 17 March 2026
- March 21, 2026 · 4.6 km
- July 23, 2026 · 8.1 km
- July 21, 2026 · 12.3 km
How we know
2 recorded sources include NOAA; independence is not established by this count.
Our own score for this event is 28 out of 100.
This is our versioned heuristic index, not source severity or a calibrated probability. Urban PEI does not count unique people.
Computed under scoring rules v4. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | Medium |
| Calamity Score (ours) | 28 / 100 |
| Legacy data-support index | 0.87/1 |
| Coordinates | 38.2356, -76.0907 |
| Nearest City | Salisbury (45 km) |
| Urban exposure index (PEI) | 32.9K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-09-04T05:42:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.1662e0b3a7ffcd85ad5bb0f9e53f522eeefc8e9f.001.1 |
Physical priority index · v4 (historical). Heuristic priority, not calibrated probability, predictive accuracy or damage. The legacy data-support index combines assigned source support and field availability. Urban PEI is distance-weighted and does not count unique people; zero does not establish that nobody is present. Model cards.
Source and revision timeline
Source: noaa. Occurrence: 2026-09-04T05:42:00.000Z.
First archived: 2026-09-04T05:46:14.254Z. Material modification: not recorded.
Retained revisions are prospective; earlier versions may be unavailable. No revision entry does not prove that a record never changed.
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Chesapeake Bay from Drum Point MD to Smith Point VA; Tidal Potomac from Indian Head to Cobb Island MD; Tidal Potomac from Cobb Island MD to Smith Point VA; Tangier Sound and the inland waters surrounding Bloodsworth Island; Delaware Bay waters south of East Point NJ to Slaughter Beach DE; Coastal waters from Cape May NJ to Cape Henlopen DE out 20 NM; Coastal waters from Cape Henlopen to Fenwick Island DE out 20 NM; Waters from Cape May NJ to Fenwick Island DE from 20 to 60 NM; Tidal Potomac from Indian Head to Cobb Island MD; Tidal Potomac from Cobb Island MD to Smith Point VA and 1 more areas |
| Headline | Special Marine Warning issued September 4 at 1:42AM EDT until September 4 at 2:45AM EDT by NWS Baltimore MD/Washington DC |
| Expires | 2026-09-04T02:45:00-04:00 |
| SenderName | NWS Baltimore MD/Washington DC |
| HasExactCoords | true |
| MergedCount | 4 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.1662e0b3a7ffcd85ad5bb0f9e53f522eeefc8e9f.001.1","noaa_urn:oid:2.49.0.1.840.0.4920b9e28b44c430595e68048998bfc165f959d0.001.1","noaa_urn:oid:2.49.0.1.840.0.8891b954f113ede98a8fefe1b5849a59db1a1584.001.1","noaa_urn:oid:2.49.0.1.840.0.6b42357ce5e01deeed4478f74533daa1088c3138.001.1"] |
| Iem TypeSummary | M |
| Iem Magnitude | 47 |
| Iem Unit | mph |
| Iem City | 8 SSW Redgate |
| Iem County | ANZ537 |
| Iem State | MD |
| Iem Wfo | LWX |
| MergedSources | [{"id":"iem_M_38.260_-76.180_1788496380000","source":"iem","severity":"low","severityValue":25,"timestamp":1788496380000,"latitude":38.26,"longitude":-76.18},{"id":"iem_M_38.130_-76.530_1788494400000","source":"iem","severity":"low","severityValue":25,"timestamp":1788494400000,"latitude":38.13,"longitude":-76.53},{"id":"iem_M_38.040_-76.320_1788496380000","source":"iem","severity":"low","severityValue":25,"timestamp":1788496380000,"latitude":38.04,"longitude":-76.32},{"id":"iem_M_38.160_-76.670_1788495300000","source":"iem","severity":"low","severityValue":25,"timestamp":1788495300000,"latitude":38.16,"longitude":-76.67}] |
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 8 March 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.
Review the area, threshold and delivery channel in your account.
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