This alert expired on 20 June 2026 at 15:00 UTC. It is kept here as a record.
It is the 220th strongest of the 391 detections recorded within 20 km of this point since 15 March 2026. Another comparable one was recorded here earlier the same day. 291 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Flood Warning issued June 18 at 9:46PM CDT until June 21 at 8:00AM CDT by NWS St Louis MO
An estimated 187,648 people live within 50 km of this point.
Nearby, since 15 March 2026
- June 24, 2026 · score 43 · 8.7 km
- June 21, 2026 · score 43 · 11.1 km
- June 11, 2026 · score 67 · 13.9 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, at 80 % 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) | 43 / 100 |
| Our confidence | 80% |
| Coordinates | 39.9519, -89.1762 |
| Nearest City | Decatur (23 km) |
| Population Exposed | 187.6K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-06-20T22:30:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Flood Warning_noaa_urn:oid:2.49.0.1.840.0.2e937e4b019acede1de9392ac4565540 |
Score Breakdown
Technical Details
| Event | Flood Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Jackson, IL; Randolph, IL; Perry, MO; Ste. Genevieve, MO; Calhoun, IL; Greene, IL; Jersey, IL; Morgan, IL; Pike, IL and 25 more areas |
| Headline | Flood Warning issued June 18 at 9:46PM CDT until June 21 at 8:00AM CDT by NWS St Louis MO |
| Expires | 2026-06-20T10:00:00-05:00 |
| SenderName | NWS St Louis MO |
| HasExactCoords | true |
| MergedCount | 32 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.2e937e4b019acede1de9392ac4565540dcb41d75.001.1","noaa_urn:oid:2.49.0.1.840.0.490a25665a8b3f6f1dc8d8efcf2248c30df5014b.004.1","noaa_urn:oid:2.49.0.1.840.0.490a25665a8b3f6f1dc8d8efcf2248c30df5014b.002.1","noaa_urn:oid:2.49.0.1.840.0.4b230504baeb0f785f2895079a157636e657f6a4.001.1","noaa_urn:oid:2.49.0.1.840.0.b9d863e79570ee94eb914225b586c912a43ce0ac.004.1","noaa_urn:oid:2.49.0.1.840.0.b9d863e79570ee94eb914225b586c912a43ce0ac.002.1","noaa_urn:oid:2.49.0.1.840.0.b9d863e79570ee94eb914225b586c912a43ce0ac.003.1","noaa_urn:oid:2.49.0.1.840.0.cb0144c420d4638129f76043abc43a2298416e4e.001.1","noaa_urn:oid:2.49.0.1.840.0.b9d863e79570ee94eb914225b586c912a43ce0ac.001.1","noaa_urn:oid:2.49.0.1.840.0.bf33c0db2e1d5eb38919dd8829c78bc0dc55ce19.005.1","noaa_urn:oid:2.49.0.1.840.0.bf33c0db2e1d5eb38919dd8829c78bc0dc55ce19.002.1","noaa_urn:oid:2.49.0.1.840.0.bf33c0db2e1d5eb38919dd8829c78bc0dc55ce19.001.1","noaa_urn:oid:2.49.0.1.840.0.bf33c0db2e1d5eb38919dd8829c78bc0dc55ce19.003.1","noaa_urn:oid:2.49.0.1.840.0.bf33c0db2e1d5eb38919dd8829c78bc0dc55ce19.004.1","noaa_urn:oid:2.49.0.1.840.0.087a1700945ceeebb4ada29e2d2e36ccd02a2392.001.1","noaa_urn:oid:2.49.0.1.840.0.55972fe999ac448b83dae1d4d48c0cb30a58a38b.001.1","noaa_urn:oid:2.49.0.1.840.0.3dc1f78f3def94bfdd0fb2b5468ee9d21c27cfea.001.1","noaa_urn:oid:2.49.0.1.840.0.462d68b90840d72489d011c284467c18491c142c.001.1","noaa_urn:oid:2.49.0.1.840.0.9a1ae43a6d0a8a1d6dd57aaac979bc4e69e377f5.001.1","noaa_urn:oid:2.49.0.1.840.0.85b6723ff742e9f6061f871096dc5b09398cc604.001.1","noaa_urn:oid:2.49.0.1.840.0.a14ddd4f04ca0ba315d9b704b3e34b897a2e54a9.002.1","noaa_urn:oid:2.49.0.1.840.0.a14ddd4f04ca0ba315d9b704b3e34b897a2e54a9.001.1","noaa_urn:oid:2.49.0.1.840.0.a14ddd4f04ca0ba315d9b704b3e34b897a2e54a9.003.1","noaa_urn:oid:2.49.0.1.840.0.490a25665a8b3f6f1dc8d8efcf2248c30df5014b.001.1","noaa_urn:oid:2.49.0.1.840.0.270cc1cb74a217731aeee82af72226c581a248f2.001.1","noaa_urn:oid:2.49.0.1.840.0.490a25665a8b3f6f1dc8d8efcf2248c30df5014b.003.1","noaa_urn:oid:2.49.0.1.840.0.b12b666e8193e16eb06bc9fb24eb9ce2fda8911d.001.1","noaa_urn:oid:2.49.0.1.840.0.b12b666e8193e16eb06bc9fb24eb9ce2fda8911d.002.1","noaa_urn:oid:2.49.0.1.840.0.b12b666e8193e16eb06bc9fb24eb9ce2fda8911d.004.1","noaa_urn:oid:2.49.0.1.840.0.b12b666e8193e16eb06bc9fb24eb9ce2fda8911d.003.1","noaa_urn:oid:2.49.0.1.840.0.b12b666e8193e16eb06bc9fb24eb9ce2fda8911d.005.1","noaa_urn:oid:2.49.0.1.840.0.a14ddd4f04ca0ba315d9b704b3e34b897a2e54a9.004.1"] |
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 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 Decatur?
Calamity.live data shows a weather event with CalamityScore 43/100, near Decatur (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.