This alert expired on 10 August 2026 at 00:45 UTC. It is kept here as a record.
No stronger detection stands among the 73 recorded within 20 km of this point since 16 March 2026 — 2 others scored the same. 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: Tornado Warning issued August 9 at 8:12PM EDT until August 9 at 8:45PM EDT by NWS Northern Indiana
An estimated 394,841 people live within 50 km of this point.
Nearby, since 16 March 2026
- July 3, 2026 · score 43 · 14.2 km
- September 4, 2026 · score 37 · 15.3 km
- September 3, 2026 · score 37 · 15.3 km
How we know
Confirmed by 2 independent sources, including NOAA.
Our own score for this event is 67 out of 100, at 86 % 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 | Critical |
| Calamity Score (ours) | 67 / 100 |
| Our confidence | 86% |
| Coordinates | 41.5740, -83.9840 |
| Nearest City | Sylvania (28 km) |
| Population Exposed | 394.8K within 50 km |
| Impact Tier | severe |
| Timestamp | 2026-08-10T00:12:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.913af90bccc53bc9d899f256448446c83eae45dc.001.1 |
Score Breakdown
Technical Details
| Event | Tornado Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Fulton, OH |
| Headline | Tornado Warning issued August 9 at 8:12PM EDT until August 9 at 8:45PM EDT by NWS Northern Indiana |
| Expires | 2026-08-09T20:45:00-04:00 |
| SenderName | NWS Northern Indiana |
| HasExactCoords | true |
| Iem TypeSummary | G |
| Iem Magnitude | 63 |
| Iem Unit | MPH |
| Iem City | 3 NW Brunersburg |
| Iem County | Defiance |
| Iem State | OH |
| Iem Wfo | IWX |
| Iem Remark | ASOS station KDFI Defiance. |
| MergedSources | [{"id":"iem_G_41.330_-84.430_1786319580000","source":"iem","severity":"low","severityValue":25,"timestamp":1786319580000,"latitude":41.33,"longitude":-84.43}] |
Safety Information
If a tornado warning is issued: go to a basement or an interior room on the lowest floor, away from windows. A vehicle and a mobile home are not shelter. Cover your head and neck. Wait for the official all-clear before going outside, and watch for downed power lines and gas leaks afterwards.
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 Sylvania?
Calamity.live data shows a weather event with CalamityScore 67/100, near Sylvania (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.