Right now
The most recent data we hold from NOAA arrived 7 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 May 2026 at 00:00 UTC. It is kept here as a record.
It is the 16th strongest of the 155 detections recorded within 20 km of this point since 11 March 2026. The last comparable one was on 19 May 2026. 3 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Watch issued May 20 at 12:40PM EDT until May 20 at 8:00PM EDT by NWS State College PA
An estimated 29,201 people live within 50 km of this point.
Nearby, since 11 March 2026
- September 4, 2026 · score 28 · 0.0 km
- September 2, 2026 · score 46 · 0.0 km
- August 28, 2026 · score 28 · 0.0 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 34 out of 100, at 80 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
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) | 34 / 100 |
| Our confidence | 80% |
| Coordinates | 41.2000, -77.2000 |
| Nearest City | Williamsport (17 km) |
| Population Exposed | 29.2K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-20T16:40:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.341bc9db029a7f15d3d7652b17fdeaa5a3a760bf.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Watch |
| Urgency | Future |
| Certainty | Possible |
| AreaDesc | Adams, PA; Bedford, PA; Columbia, PA; Cumberland, PA; Dauphin, PA; Franklin, PA; Fulton, PA; Huntingdon, PA; Juniata, PA; Lancaster, PA; Lebanon, PA; Mifflin, PA; Northumberland, PA; Perry, PA; Schuylkill, PA; Snyder, PA; Somerset, PA; York, PA |
| Headline | Severe Thunderstorm Watch issued May 20 at 12:40PM EDT until May 20 at 8:00PM EDT by NWS State College PA |
| Expires | 2026-05-20T20:00:00-04:00 |
| SenderName | NWS State College PA |
| HasExactCoords | false |
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.
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