Right now
The most recent data we hold from NOAA arrived 9 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 18 May 2026 at 22:31 UTC. It is kept here as a record.
It is the 84th strongest of the 193 detections recorded within 20 km of this point since 13 May 2026. Another comparable one was recorded here earlier the same day. 9 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued May 18 at 6:21PM EDT until May 18 at 6:30PM EDT by NWS Baltimore MD/Washington DC
Urban PEI: 224,378 within a heuristic 50 km radius; not unique people.
Nearby, since 13 May 2026
- May 13, 2026 · score 43 · 3.9 km
- August 27, 2026 · score 49 · 5.2 km
- August 27, 2026 · score 49 · 14.1 km
How we know
6 recorded sources include NOAA; independence is not established by this count.
Our own score for this event is 43 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 v1. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | Medium |
| Calamity Score (ours) | 43 / 100 |
| Legacy data-support index | 0.90/1 |
| Coordinates | 39.4200, -77.9900 |
| Nearest City | Martinsburg (5 km) |
| Urban exposure index (PEI) | 224.4K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-18T22:21:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.3874578ac094306c1859fc794cccf87f5604aede.001.1 |
Physical priority index · v1. 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: 2026-05-18T22:21:00.000Z.
First archived: 2026-05-18T22:26:22.410Z. 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 | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Berkeley, WV; Jefferson, WV |
| Headline | Severe Thunderstorm Warning issued May 18 at 6:21PM EDT until May 18 at 6:30PM EDT by NWS Baltimore MD/Washington DC |
| Expires | 2026-05-18T18:31:00-04:00 |
| SenderName | NWS Baltimore MD/Washington DC |
| HasExactCoords | true |
| Iem TypeSummary | D |
| Iem City | Forest Park |
| Iem County | Washington |
| Iem State | MD |
| Iem Wfo | LWX |
| Iem Remark | Multiple trees down on High Germany Road and Bottenfield Road. |
| MergedSources | [{"id":"iem_H_39.160_-78.400_1779138600000","source":"iem","severity":"low","severityValue":25,"timestamp":1779138600000,"latitude":39.16,"longitude":-78.4},{"id":"iem_D_39.200_-78.150_1779140880000","source":"iem","severity":"low","severityValue":25,"timestamp":1779140880000,"latitude":39.2,"longitude":-78.15},{"id":"iem_D_39.160_-78.340_1779139200000","source":"iem","severity":"low","severityValue":25,"timestamp":1779139200000,"latitude":39.16,"longitude":-78.34},{"id":"iem_D_39.160_-78.350_1779139200000","source":"iem","severity":"low","severityValue":25,"timestamp":1779139200000,"latitude":39.16,"longitude":-78.35},{"id":"iem_D_39.700_-78.300_1779138960000","source":"iem","severity":"low","severityValue":25,"timestamp":1779138960000,"latitude":39.7,"longitude":-78.3}] |
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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