Walworth County was hit as recently as 2026-07-07, 24 days ago. Walworth County is hit in most years, and usually several times over. The largest stone on record here is 3 inches, a teacup and 3 times the National Weather Service's 1 inch severe criterion, reported on 2018-08-23 near Hoven.
Colored swath = NOAA MRMS radar-estimated hail size; dots = NOAA SPC reports in South Dakota. Radar-indicated, not a guarantee of damage.
The last hail here fell on 2026-07-07, around Selby. A free SwathIQ account -- hand-reviewed, invite within 24-48h -- pulls Walworth County addresses inside a hail swath above your size threshold into a door-knock list you can export, scoped to your approved markets.
Get free access Check an addressOur US-based call center calls the homeowners in this storm and books roof inspections straight onto your calendar. You work the storm; we fill the schedule. We dial -- you do not have to knock a single door.
See call-center options ->NOAA's Storm Prediction Center has logged 39 separate hail days here since 2010 -- 2.3 a year over 17 years of record. Those days carry 90 separate reports between them, two or three on a typical one. Exactly one year since 2010 passed with no reported hail day at all. The busiest single year was 2016, with 5 hail days. The last five years have been quieter than the long run: 7 days since 2022, against 2.7 a year before that.
6 of the 39 days reached 2 inches or more -- 15%, or about one hail day in 6, the last on 2021-08-27. They land in the same month as everything else, August. 12 of the 39 days reached golf-ball size, 1.75 inches or bigger.
Across the whole of South Dakota, see the South Dakota hail map and history.
Reports cluster nearest Selby -- 13 of the county's 39 hail days -- then Java (8), Lowry (7), Glenham (7) and Akaska (5). Beyond those, NOAA names Mobridge, Hoven and Bowdle on more than one hail day apiece.
| Place | Hail days since 2010 | Largest stone |
|---|---|---|
| Selby | 5 | 1.75″ |
| Java | 4 | 1.75″ |
| 2 N Hoven | 3 | 1.75″ |
| Mobridge | 3 | 1.50″ |
| Glenham | 3 | 1.25″ |
The season runs June through August: 34 of the 39 hail days on record fall in those 3 months (87%). August is the single busiest month, with 13 of them (33%). That peak closes the window: the season builds all the way to its worst month and then stops. Hail has also been reported in May and September, outside that window. Reports span 5 of the 12 calendar months; the other 7 have never produced one.
| Month | Hail days |
|---|---|
| May | 3 |
| June | 10 |
| July | 11 |
| August | 13 |
| September | 2 |
That day put 1 report on the map, the biggest 1 inch near Selby. 2 hail days have already been reported this year.
| Date | Max hail | Reports |
|---|---|---|
| 2026-07-07 | 1.00″ | 1 |
| 2026-06-02 | 1.00″ | 1 |
| 2025-08-13 | 1.00″ | 1 |
| 2025-08-05 | 1.00″ | 1 |
| 2025-06-21 | 1.00″ | 1 |
| 2023-07-30 | 1.75″ | 2 |
| 2022-06-24 | 1.00″ | 1 |
| 2021-08-27 | 2.50″ | 3 |
The colored swath is NOAA's MRMS radar estimate of the largest hail per ~1 km cell; the dots are SPC ground reports. Yellow is about an inch, red 1.5 to 2″, purple 2″ and up (hail size vs roof damage). On this county's worst day the reports reached 3 inches, which is the purple band. Look up a street address with the hail history by address tool.
The nearest counties with a page of their own: Campbell County (28 hail days), Potter County (27) and Edmunds County (42). Walworth County sits in between.
Campbell County · Potter County · Edmunds County
Back to the South Dakota hail map or the U.S. hail map.
Data & method: NOAA/NWS Storm Prediction Center reports + NOAA MRMS MESH radar, Walworth County, South Dakota only. Radar-indicated and observation-based -- informational only, not a guarantee of damage or a valid claim.