Right now
The most recent data we hold from NOAA arrived 29 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 23 May 2026 at 22:45 UTC. It is kept here as a record.
It is the 13th strongest of the 32 detections recorded within 20 km of this point since 20 May 2026. Another comparable one was recorded here earlier the same day. 5 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Flash Flood Warning issued May 23 at 3:51PM CDT until May 23 at 5:45PM CDT by NWS Houston/Galveston TX
Urban PEI: 804,236 within a heuristic 50 km radius; not unique people.
Nearby, since 20 May 2026
- July 23, 2026 · score 48 · 11.0 km
- August 29, 2026 · score 52 · 11.2 km
- August 28, 2026 · score 52 · 13.7 km
How we know
5 recorded sources include NOAA; independence is not established by this count.
Our own score for this event is 48 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) | 48 / 100 |
| Legacy data-support index | 0.89/1 |
| Coordinates | 29.3169, -95.1960 |
| Nearest City | Alvin (12 km) |
| Urban exposure index (PEI) | 804.2K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-23T20:51:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Flash Flood Warning_noaa_urn:oid:2.49.0.1.840.0.04b4bc0517cb9e935a366d1fca3a080d |
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: 2026-05-23T20:51:00.000Z.
First archived: 2026-05-23T21:12:37.773Z. 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 | Flash Flood Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Brazoria, TX; Galveston, TX |
| Headline | Flash Flood Warning issued May 23 at 3:51PM CDT until May 23 at 5:45PM CDT by NWS Houston/Galveston TX |
| Expires | 2026-05-23T17:45:00-05:00 |
| SenderName | NWS Houston/Galveston TX |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.04b4bc0517cb9e935a366d1fca3a080d80424bb5.001.1","noaa_urn:oid:2.49.0.1.840.0.d411f000dd91a111ac740f1f953ada6876e0a624.001.1"] |
| Iem TypeSummary | F |
| Iem City | Hillcrest |
| Iem County | Brazoria |
| Iem State | TX |
| Iem Wfo | HGX |
| Iem Remark | Estimated 4 inches of water in Hillcrest, TX. |
| Google News RssFeed | weather |
| Google News SourceName | KHOU |
| MergedSources | [{"id":"iem_M_29.360_-94.720_1779561000000","source":"iem","severity":"low","severityValue":25,"timestamp":1779561000000,"latitude":29.36,"longitude":-94.72},{"id":"iem_W_29.270_-94.820_1779554100000","source":"iem","severity":"low","severityValue":25,"timestamp":1779554100000,"latitude":29.27,"longitude":-94.82},{"id":"iem_F_29.390_-95.220_1779562200000","source":"iem","severity":"low","severityValue":25,"timestamp":1779562200000,"latitude":29.39,"longitude":-95.22},{"id":"gnews_weather_494324_150","source":"google_news","severity":"medium","severityValue":40,"timestamp":1779569940000,"latitude":29.76,"longitude":-95.36}] |
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.
Review the area, threshold and delivery channel in your account.
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