Right now
The most recent data we hold from NOAA arrived 66 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 27 May 2026 at 19:04 UTC. It is kept here as a record.
No stronger detection stands among the 13 recorded within 20 km of this point since 16 April 2026 — 8 others scored the same. Another comparable one was recorded here earlier the same day. One more was recorded here in the fortnight before it.
What the source measured
NOAA reported: Flash Flood Warning issued May 27 at 1:54PM CDT until May 27 at 2:00PM CDT by NWS Fort Worth TX
An estimated 81,103 people live within 50 km of this point.
Nearby, since 16 April 2026
- May 10, 2026 · score 39 · 7.8 km
- August 8, 2026 · score 39 · 15.7 km
- June 23, 2026 · score 39 · 19.7 km
How we know
Confirmed by 4 independent sources, including NOAA.
Our own score for this event is 39 out of 100, at 89 % 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 | 89% |
| Coordinates | 33.7060, -96.3470 |
| Nearest City | Denison (19 km) |
| Population Exposed | 81.1K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-27T18:54:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.f3716aa4bcc80cd110feb2e4c3dd61390aa24b0c.001.1 |
Score Breakdown
Technical Details
| Event | Flash Flood Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Fannin, TX; Grayson, TX |
| Headline | Flash Flood Warning issued May 27 at 1:54PM CDT until May 27 at 2:00PM CDT by NWS Fort Worth TX |
| Expires | 2026-05-27T14:04:00-05:00 |
| SenderName | NWS Fort Worth TX |
| HasExactCoords | true |
| Iem TypeSummary | F |
| Iem City | Trenton |
| Iem County | Fannin |
| Iem State | TX |
| Iem Wfo | FWD |
| Iem Remark | Flash flooding impacting Highway 121 and adjacent roads in Trenton. |
| MergedSources | [{"id":"iem_F_33.090_-96.630_1779898020000","source":"iem","severity":"low","severityValue":25,"timestamp":1779898020000,"latitude":33.09,"longitude":-96.63},{"id":"iem_F_33.380_-96.350_1779898500000","source":"iem","severity":"low","severityValue":25,"timestamp":1779898500000,"latitude":33.38,"longitude":-96.35},{"id":"iem_F_33.430_-96.340_1779903000000","source":"iem","severity":"low","severityValue":25,"timestamp":1779903000000,"latitude":33.43,"longitude":-96.34}] |
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 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.
Want to know when something happens near Denison?
Calamity.live data shows a weather event with CalamityScore 39/100, near Denison (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.