Right now
The most recent data we hold from NOAA arrived 80 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 21 July 2026 at 18:30 UTC. It is kept here as a record.
It is the 22nd strongest of the 40 detections recorded within 20 km of this point since 27 May 2026. The last comparable one was on 6 July 2026.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued July 21 at 2:19PM EDT until July 21 at 2:30PM EDT by NWS Baltimore MD/Washington DC
Urban PEI: 41,517 within a heuristic 50 km radius; not unique people.
Nearby, since 27 May 2026
- September 20, 2026 · 13.7 km
- September 10, 2026 · 15.5 km
- August 5, 2026 · score 43 · 17.4 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
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 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) | 28 / 100 |
| Legacy data-support index | 0.80/1 |
| Coordinates | 38.7589, -83.0750 |
| Nearest City | Portsmouth (7 km) |
| Urban exposure index (PEI) | 41.5K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-21T18:19:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.0565eebc7bda89a35ef8d158bcc3a7a5 |
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: 2026-07-21T18:19:00.000Z.
First archived: 2026-07-21T18:22:36.113Z. 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 | Albemarle, VA; Nelson, VA; Lewis, WV; Upshur, WV; Amherst, VA and 12 more areas |
| Headline | Severe Thunderstorm Warning issued July 21 at 2:19PM EDT until July 21 at 2:30PM EDT by NWS Baltimore MD/Washington DC |
| Expires | 2026-07-21T14:30:00-04:00 |
| SenderName | NWS Baltimore MD/Washington DC |
| HasExactCoords | true |
| MergedCount | 15 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.0565eebc7bda89a35ef8d158bcc3a7a5d49feaf8.002.1","noaa_urn:oid:2.49.0.1.840.0.ab9e5982dc4e76b1a23dd1d8a5e795e94587a7c5.001.1","noaa_urn:oid:2.49.0.1.840.0.28835821b7ac9cd0d55c29f78e71634d0b490ae3.002.1","noaa_urn:oid:2.49.0.1.840.0.c93783301c58a11dea7fdb7de48d3ff4d0d75d47.001.1","noaa_urn:oid:2.49.0.1.840.0.7a1a08e1ae26c4b0d0f77f1b26f3abcc26fffe32.001.1","noaa_urn:oid:2.49.0.1.840.0.b173bf15f0765ea8b916c3b05d88b58af1ca61f3.001.1","noaa_urn:oid:2.49.0.1.840.0.e52c4e633bb394fd3fa406e38a2a1ea2f963886f.002.1","noaa_urn:oid:2.49.0.1.840.0.70fadcbbf73a67df567f1cd43ee76f5e3ed522a8.001.1","noaa_urn:oid:2.49.0.1.840.0.871193deacb43c684188d72b97359ac063def968.001.1","noaa_urn:oid:2.49.0.1.840.0.d1b74e43c4ca77ffad1420a01fcb0ef3441cdff8.002.1","noaa_urn:oid:2.49.0.1.840.0.e7fd96a3abe1ffd779cd8adc0f5944ba285eb1ba.001.1","noaa_urn:oid:2.49.0.1.840.0.a77ad9646adb09dafbaa12ba88c7edae5f149705.001.1","noaa_urn:oid:2.49.0.1.840.0.8e8ae3bfc846fa3c98330b71caf564d75fff11a6.001.1","noaa_urn:oid:2.49.0.1.840.0.f9d3503a7f3e62a3ee4c0728633132b04200ccab.002.1","noaa_urn:oid:2.49.0.1.840.0.f60a5da5319bc5b98aa1551c7347b410b655fb59.001.1"] |
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.
Want to know when something happens near Portsmouth?