Verified storm · active
1.9–3.6" hail crossed Dewey County, SD — August 30, 2026
Measured against the NOAA MRMS national radar feed on its 2-minute cycle — a verified event, not a forecast.
Storm stats
| County | Dewey County, SD |
|---|---|
| Max hail (MESH) | 3.6" |
| Mean hail (MESH) | 1.9" |
| Swath area | 383 mi² (991 km²) |
| Radar cells (~1 km grid) | 1,135 |
| First radar detection | 2026-08-30 02:46 UTC |
| Last radar detection | 2026-08-30 05:30 UTC |
| Verified | 2026-08-30 02:48 UTC |
| Swath centroid | 44.9657, -100.8197 |
| Storm ID | sw_c09576f6 |
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Dewey County, SD — verified storm record
Swath has 31 radar-verified hail storms on record for Dewey County, SD going back to July 2025, the largest measuring 3.59″. Every one was measured against NOAA MRMS radar — not estimated, and not a forecast.