This alert expired on 11 August 2026 at 15:15 UTC. It is kept here as a record.
It is the 4th strongest of the 30 detections recorded within 20 km of this point since 16 March 2026. Another comparable one was recorded here earlier the same day. 4 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued August 11 at 9:16AM CDT until August 11 at 10:15AM CDT by NWS Chicago IL
An estimated 80,916 people live within 50 km of this point.
Nearby, since 16 March 2026
- August 11, 2026 · score 39 · 6.7 km
- July 3, 2026 · score 43 · 11.3 km
How we know
Confirmed by 5 independent sources, including NOAA.
Our own score for this event is 39 out of 100, at 92 % 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 | 92% |
| Coordinates | 42.0352, -89.7211 |
| Nearest City | Sterling (27 km) |
| Population Exposed | 80.9K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-11T14:16:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.f1646ff304ac05aafdac5fb168afb640 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Lee, IL; Ogle, IL; Winnebago, IL; Stephenson, IL; Bureau, IL; Henry, IL and 2 more areas |
| Headline | Severe Thunderstorm Warning issued August 11 at 9:16AM CDT until August 11 at 10:15AM CDT by NWS Chicago IL |
| Expires | 2026-08-11T10:15:00-05:00 |
| SenderName | NWS Chicago IL |
| HasExactCoords | true |
| MergedCount | 5 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.f1646ff304ac05aafdac5fb168afb64053d1a0b2.001.1","noaa_urn:oid:2.49.0.1.840.0.d780344ae69e40db6261b13882c7e187617fc078.002.1","noaa_urn:oid:2.49.0.1.840.0.61c0d315d6198bb6c295e0771ec4638b9fd80155.002.1","noaa_urn:oid:2.49.0.1.840.0.e801781b8f3782d4efc94e951984539c38e72532.001.1","noaa_urn:oid:2.49.0.1.840.0.5c65c9a9924436e547d5bfdd29d3fdfff7fe4955.001.1"] |
| Iem TypeSummary | D |
| Iem City | Clinton |
| Iem County | Clinton |
| Iem State | IA |
| Iem Wfo | DVN |
| Iem Remark | Storm door on garage was removed from its frame. Lots of tree branches down, including some large. |
| MergedSources | [{"id":"iem_D_42.250_-90.270_1786455000000","source":"iem","severity":"low","severityValue":25,"timestamp":1786455000000,"latitude":42.25,"longitude":-90.27},{"id":"iem_G_42.350_-90.010_1786456560000","source":"iem","severity":"low","severityValue":25,"timestamp":1786456560000,"latitude":42.35,"longitude":-90.01},{"id":"iem_D_42.230_-89.880_1786456080000","source":"iem","severity":"low","severityValue":25,"timestamp":1786456080000,"latitude":42.23,"longitude":-89.88},{"id":"iem_D_41.840_-90.230_1786456260000","source":"iem","severity":"low","severityValue":25,"timestamp":1786456260000,"latitude":41.84,"longitude":-90.23}] |
Safety Information
Always follow official guidance from your local emergency management agency. This platform provides scientific monitoring data and is not a substitute for official warnings. If you are in immediate danger, contact your local emergency number.
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 Sterling?
Calamity.live data shows a weather event with CalamityScore 39/100, near Sterling (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.