This alert expired on 25 May 2026 at 21:30 UTC. It is kept here as a record.
It is the 20th strongest of the 26 detections recorded within 20 km of this point since 16 March 2026. Another comparable one was recorded here earlier the same day. 3 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Flash Flood Warning issued May 25 at 4:04PM EDT until May 25 at 5:30PM EDT by NWS Columbia SC
Nearby, since 16 March 2026
- July 14, 2026 · score 43 · 16.7 km
- June 1, 2026 · score 39 · 18.2 km
- March 17, 2026 · score 43 · 19.5 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 22 out of 100, at 60 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Event Data
| Type | Severe weather |
| Severity | medium |
| Calamity Score (ours) | 22 / 100 |
| Our confidence | 60% |
| Coordinates | 34.5107, -80.7707 |
| Nearest City | Rock Hill (51 km) |
| Impact Tier | minor |
| Timestamp | 2026-05-25T20:04:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.956fa6f1d343aaea95ab62e99ba76d6a70a28618.001.1 |
Score Breakdown
Technical Details
| Event | Flash Flood Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Chesterfield, SC; Fairfield, SC; Kershaw, SC; Lancaster, SC; Richland, SC |
| Headline | Flash Flood Warning issued May 25 at 4:04PM EDT until May 25 at 5:30PM EDT by NWS Columbia SC |
| Expires | 2026-05-25T17:30:00-04:00 |
| SenderName | NWS Columbia SC |
| HasExactCoords | true |
Safety Information
During flooding: never walk, swim, or drive through floodwaters. Six inches of moving water can knock you down, and one foot of water can sweep away a vehicle. Move to higher ground if waters rise. After flooding, avoid contact with floodwater which may contain sewage, chemicals, or debris. Follow local emergency service guidance.
Series begins 10 February 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.
Want to know when something happens near Rock Hill?
Calamity.live data shows a weather event with CalamityScore 22/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 187 scientific monitoring sources.