This alert expired on 10 August 2026 at 12:45 UTC. It is kept here as a record.
It is the 2nd strongest of the 68 detections recorded within 20 km of this point since 11 March 2026. 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: Special Marine Warning issued August 10 at 8:27AM EDT until August 10 at 8:45AM EDT by NWS Cleveland OH
An estimated 1,496,015 people live within 50 km of this point.
Nearby, since 11 March 2026
- July 5, 2026 · score 52 · 2.8 km
- September 3, 2026 · score 46 · 4.3 km
- May 19, 2026 · score 52 · 4.3 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 52 out of 100, at 82 % 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) | 52 / 100 |
| Our confidence | 82% |
| Coordinates | 41.6604, -81.8241 |
| Nearest City | Rocky River (20 km) |
| Population Exposed | 1.5M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-10T12:27:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Special Marine Warning_noaa_urn:oid:2.49.0.1.840.0.39ff769064bc6dee88743dfc9f725279 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Vermilion to Avon Point OH; Vermilion to Avon Point OH beyond 5 nm off shoreline to US-Canadian border; Avon Point to Willowick OH; Willowick to Geneva-on-the Lake OH; Avon Point to Willowick OH beyond 5 nm off shoreline to US-Canadian border; Willowick to Geneva-on-the-Lake OH beyond 5NM off shoreline to US-Canadian border |
| Headline | Special Marine Warning issued August 10 at 8:27AM EDT until August 10 at 8:45AM EDT by NWS Cleveland OH |
| Expires | 2026-08-10T08:45:00-04:00 |
| SenderName | NWS Cleveland OH |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.39ff769064bc6dee88743dfc9f725279297a60d5.002.1","noaa_urn:oid:2.49.0.1.840.0.8743dc4a5dbb34f72f600612a3da8aab3911b89f.001.1"] |
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 Rocky River?
Calamity.live data shows a weather event with CalamityScore 52/100, near Rocky River (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.