Right now
The most recent data we hold from NOAA arrived 6 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 19:45 UTC. It is kept here as a record.
It is the 9th strongest of the 37 detections recorded within 20 km of this point since 15 March 2026. The last comparable one was on 21 May 2026. 19 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Flood Warning issued May 20 at 2:45PM CDT until May 21 at 6:27PM CDT by NWS Kansas City/Pleasant Hill MO
Urban PEI: 429,137 within a heuristic 50 km radius; not unique people.
Nearby, since 15 March 2026
- May 22, 2026 · score 43 · 0.0 km
- May 21, 2026 · score 48 · 5.4 km
- June 1, 2026 · score 43 · 13.0 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 43 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) | 43 / 100 |
| Legacy data-support index | 0.79/1 |
| Coordinates | 39.0707, -90.7437 |
| Nearest City | O'Fallon (29 km) |
| Urban exposure index (PEI) | 429.1K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-22T04:17:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Flood Warning_noaa_urn:oid:2.49.0.1.840.0.09bd918f7d2ffa2b58f220a50a4833ab |
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: 2026-05-22T04:17:00.000Z.
First archived: 2026-05-20T21:33:50.190Z. 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 | Flood Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Bates, MO; Cass, MO; Henry, MO; Cass, MO; Henry, MO; Johnson, MO; Callaway, MO; Osage, MO and 39 more areas |
| Headline | Flood Warning issued May 20 at 2:45PM CDT until May 21 at 6:27PM CDT by NWS Kansas City/Pleasant Hill MO |
| Expires | 2026-05-21T14:45:00-05:00 |
| SenderName | NWS Kansas City/Pleasant Hill MO |
| HasExactCoords | true |
| MergedCount | 46 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.09bd918f7d2ffa2b58f220a50a4833ab5c8c4e44.001.1","noaa_urn:oid:2.49.0.1.840.0.09bd918f7d2ffa2b58f220a50a4833ab5c8c4e44.002.1","noaa_urn:oid:2.49.0.1.840.0.361c1ed1fa8fd2969ff31bb1a8512c75b3164c96.001.1","noaa_urn:oid:2.49.0.1.840.0.da02e6c61a7fe2720eda156db8fd5e014c8581c5.001.1","noaa_urn:oid:2.49.0.1.840.0.f2600d8115763e6e8c0847bc17c191ed3f1698c6.001.1","noaa_urn:oid:2.49.0.1.840.0.b9b5caa5456476ffe2f16fc632f97310a14a1638.001.1","noaa_urn:oid:2.49.0.1.840.0.59030682c609e0ef1eea95bf6f66d418689586bb.001.1","noaa_urn:oid:2.49.0.1.840.0.59030682c609e0ef1eea95bf6f66d418689586bb.004.1","noaa_urn:oid:2.49.0.1.840.0.59030682c609e0ef1eea95bf6f66d418689586bb.002.1","noaa_urn:oid:2.49.0.1.840.0.59030682c609e0ef1eea95bf6f66d418689586bb.003.1","noaa_urn:oid:2.49.0.1.840.0.59030682c609e0ef1eea95bf6f66d418689586bb.005.1","noaa_urn:oid:2.49.0.1.840.0.a7f527bc079e695d0cb6b9d590705a6de97c5d10.005.1","noaa_urn:oid:2.49.0.1.840.0.a7f527bc079e695d0cb6b9d590705a6de97c5d10.001.1","noaa_urn:oid:2.49.0.1.840.0.a7f527bc079e695d0cb6b9d590705a6de97c5d10.004.1","noaa_urn:oid:2.49.0.1.840.0.a7f527bc079e695d0cb6b9d590705a6de97c5d10.002.1","noaa_urn:oid:2.49.0.1.840.0.a7f527bc079e695d0cb6b9d590705a6de97c5d10.003.1","noaa_urn:oid:2.49.0.1.840.0.bb9a5205a2eb34f619aa6e8852df598eb07a0878.001.1","noaa_urn:oid:2.49.0.1.840.0.285227f5598727227cd2e1dfb4114e27859a4004.001.1","noaa_urn:oid:2.49.0.1.840.0.0cfbe74f43bf96e8434d70bd32597e80978507f9.001.1","noaa_urn:oid:2.49.0.1.840.0.bed9b5b508b2b37416a593decec2d87f36bbc6d3.001.1","noaa_urn:oid:2.49.0.1.840.0.bed9b5b508b2b37416a593decec2d87f36bbc6d3.002.1","noaa_urn:oid:2.49.0.1.840.0.5680dee3e366175c42bbc8efefc4fe8bf0d8f89c.002.1","noaa_urn:oid:2.49.0.1.840.0.5680dee3e366175c42bbc8efefc4fe8bf0d8f89c.001.1","noaa_urn:oid:2.49.0.1.840.0.1d9540202982a04aa904859c8aa08f42af9c451d.001.1","noaa_urn:oid:2.49.0.1.840.0.8ff8bb36d523a7db4c0223a80374170006ba1d78.001.1","noaa_urn:oid:2.49.0.1.840.0.905df4758e94f9fded650802649fc60814adb84c.001.1","noaa_urn:oid:2.49.0.1.840.0.905df4758e94f9fded650802649fc60814adb84c.002.1","noaa_urn:oid:2.49.0.1.840.0.2aabb1f4cf1a0ec5914436becd928561fd4cd4be.001.1","noaa_urn:oid:2.49.0.1.840.0.437920734f5fe5effca345efea95064e0d4e2c32.003.1","noaa_urn:oid:2.49.0.1.840.0.437920734f5fe5effca345efea95064e0d4e2c32.005.1","noaa_urn:oid:2.49.0.1.840.0.437920734f5fe5effca345efea95064e0d4e2c32.004.1","noaa_urn:oid:2.49.0.1.840.0.437920734f5fe5effca345efea95064e0d4e2c32.002.1","noaa_urn:oid:2.49.0.1.840.0.437920734f5fe5effca345efea95064e0d4e2c32.001.1","noaa_urn:oid:2.49.0.1.840.0.aac7268dcb11da622ce6c4428f6634b534be94cd.001.1","noaa_urn:oid:2.49.0.1.840.0.1fbff4a434ae70f134160050218e065f86cf857a.001.1","noaa_urn:oid:2.49.0.1.840.0.d27e94a437359a5e5d54f0311320eb1bc8af150a.001.1","noaa_urn:oid:2.49.0.1.840.0.572ea39e15acf4e2c9316b725dee0c5c6f6afa8b.001.1","noaa_urn:oid:2.49.0.1.840.0.00ce4b41f16046c97bd76fdfd53e412dd5fe61b8.001.1","noaa_urn:oid:2.49.0.1.840.0.c0b8d3b6e6f9eee8f208d169335f2bcac88a7e43.001.1","noaa_urn:oid:2.49.0.1.840.0.5b0e469c414a8ce5b3b7a7fc3d95f21c77136ec8.001.1","noaa_urn:oid:2.49.0.1.840.0.bcbb54022a27da1b27c576fc51938b47663e203c.001.1","noaa_urn:oid:2.49.0.1.840.0.bcbb54022a27da1b27c576fc51938b47663e203c.002.1","noaa_urn:oid:2.49.0.1.840.0.bcbb54022a27da1b27c576fc51938b47663e203c.003.1","noaa_urn:oid:2.49.0.1.840.0.bcbb54022a27da1b27c576fc51938b47663e203c.005.1","noaa_urn:oid:2.49.0.1.840.0.bcbb54022a27da1b27c576fc51938b47663e203c.004.1","noaa_urn:oid:2.49.0.1.840.0.437920734f5fe5effca345efea95064e0d4e2c32.006.1"] |
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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