Reported by SPC today.
It is the 22nd strongest of the 44 detections recorded within 20 km of this point since 18 May 2026. Another comparable one was recorded here earlier the same day.
What the source measured
SPC reported: Wind UNK kt near Alcester, Union, SD. EM reported multiple large tree branches down of 3 inches and greater. Also reported multiple power lines down. Suspected power lines were brought down by the trees. Ti (FSD)
Nearby, since 18 May 2026
- June 1, 2026 · score 46 · 16.9 km
- June 1, 2026 · score 67 · 24.0 km
How we know
Confirmed by 2 independent sources, including SPC.
Our own score for this event is 16 out of 100, at 66 % 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) | 16 / 100 |
| Our confidence | 66% |
| Coordinates | 43.0300, -96.6300 |
| Nearest City | Sioux Falls (57 km) |
| Impact Tier | minor |
| Timestamp | 2026-09-02T02:25:00.000Z |
| Source | https://www.spc.noaa.gov/climo/reports/today.html |
Score Breakdown
Technical Details
| ReportType | wind |
| Speed | UNK |
| Location | Alcester |
| County | Union |
| State | SD |
| Comments | EM reported multiple large tree branches down of 3 inches and greater. Also reported multiple power lines down. Suspected power lines were brought down by the trees. Ti (FSD) |
| Iem TypeSummary | D |
| Iem City | Alcester |
| Iem County | Union |
| Iem State | SD |
| Iem Wfo | FSD |
| Iem Remark | EM reported multiple large tree branches down of 3 inches and greater. Also reported multiple power lines down. Suspected power lines were brought down by the trees. Timing aligns well with radar velo |
| MergedSources | [{"id":"iem_D_43.030_-96.630_1788315900000","source":"iem","severity":"low","severityValue":25,"timestamp":1788315900000,"latitude":43.03,"longitude":-96.63}] |
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 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 in this area?
Calamity.live data shows a weather event with CalamityScore 16/100 (United States), based on data from spc. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.