The most recent reported hail day was 2026-04-17, 105 days ago. Waukesha County has recorded hail in nearly every year on the archive. 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 2015-08-02 near Mukwonago.
Colored swath = NOAA MRMS radar-estimated hail size; dots = NOAA SPC reports in Wisconsin. Radar-indicated, not a guarantee of damage.
The last hail here fell on 2026-04-17, around Eagle. A free SwathIQ account -- hand-reviewed, invite within 24-48h -- pulls Waukesha 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 33 separate hail days here since 2010 -- 1.9 a year over 17 years of record. Those days carry 104 separate reports between them, better than three on a typical one. 2 of those 17 years produced none at all. The busiest single year was 2014, with 4 hail days. The last five years have run hotter than the long-run rate: 13 days since 2022, against 1.7 a year before that.
5 of the 33 days reached 2 inches or more -- 15%, or about one hail day in 7, the last on 2026-04-14. Those big days do not follow the county's usual calendar: most of them fall in April, not May. 9 of the 33 days reached golf-ball size, 1.75 inches or bigger.
Across the whole of Wisconsin, see the Wisconsin hail map and history.
Reports cluster nearest Oconomowoc -- 7 of the county's 33 hail days -- then Mukwonago (6), Waukesha (6), Big Bend (5) and Hartland (4). Beyond those, NOAA names Merton, Lac La Belle, Menomonee Falls, North Prairie, Brookfield, Eagle, Muskego, Dousman and Oconomowoc Lake on more than one hail day apiece.
| Place | Hail days since 2010 | Largest stone |
|---|---|---|
| Mukwonago | 5 | 1.25″ |
| Hartland | 3 | 2.00″ |
| 2 Wsw Oconomowoc | 3 | 1.75″ |
| Brookfield | 3 | 1.75″ |
| Eagle | 3 | 1.50″ |
The season runs April through August: 27 of the 33 hail days on record fall in those 5 months (82%). May is the single busiest month, with 8 of them (24%). That peak sits inside the window rather than at either end. Hail has also been reported in February, September and November, outside that window. Reports span 8 of the 12 calendar months; the other 4 have never produced one.
| Month | Hail days |
|---|---|
| February | 1 |
| April | 6 |
| May | 8 |
| June | 6 |
| July | 3 |
| August | 4 |
| September | 4 |
| November | 1 |
That day put 2 reports on the map, the biggest 1 inch near Eagle. 2 hail days have already been reported this year.
| Date | Max hail | Reports |
|---|---|---|
| 2026-04-17 | 1.00″ | 2 |
| 2026-04-14 | 2.00″ | 8 |
| 2025-05-15 | 2.00″ | 13 |
| 2025-04-18 | 2.00″ | 12 |
| 2024-06-24 | 1.25″ | 2 |
| 2024-05-07 | 1.00″ | 4 |
| 2024-02-08 | 1.50″ | 5 |
| 2023-07-28 | 1.25″ | 1 |
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: Milwaukee County (29 hail days), Washington County (25) and Jefferson County (24). Waukesha County takes more hail than any of them.
Milwaukee County · Washington County · Jefferson County
Back to the Wisconsin hail map or the U.S. hail map.
Data & method: NOAA/NWS Storm Prediction Center reports + NOAA MRMS MESH radar, Waukesha County, Wisconsin only. Radar-indicated and observation-based -- informational only, not a guarantee of damage or a valid claim.