Right now
The most recent data we hold from NOAA arrived 8 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 1 June 2026 at 23:00 UTC. It is kept here as a record.
It is the 10th strongest of the 42 detections recorded within 20 km of this point since 16 March 2026. Another comparable one was recorded here earlier the same day. 2 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued June 1 at 6:30PM EDT until June 1 at 7:00PM EDT by NWS Greenville-Spartanburg SC
An estimated 71,548 people live within 50 km of this point.
Nearby, since 16 March 2026
- March 17, 2026 · score 39 · 10.0 km
- June 1, 2026 · score 39 · 15.8 km
- June 28, 2026 · score 43 · 16.6 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 39 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) | 39 / 100 |
| Our confidence | 80% |
| Coordinates | 34.6800, -81.0804 |
| Nearest City | Rock Hill (27 km) |
| Population Exposed | 71.5K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-06-01T22:30:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.4de80e2a2109d764b8da3253e72ea0df |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Chester, SC |
| Headline | Severe Thunderstorm Warning issued June 1 at 6:30PM EDT until June 1 at 7:00PM EDT by NWS Greenville-Spartanburg SC |
| Expires | 2026-06-01T19:00:00-04:00 |
| SenderName | NWS Greenville-Spartanburg SC |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.4de80e2a2109d764b8da3253e72ea0df622ebee1.001.1","noaa_urn:oid:2.49.0.1.840.0.603b2612d26f1ccaaa0c3f2984620985f993b794.002.1"] |
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.
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