The most recent reported hail day was 2023-05-22 -- 3 years ago, with nothing reported since. Powell County is hit in most years. The largest stone on record here is 1.75 inches, a golf ball and 1.8 times the National Weather Service's 1 inch severe criterion, reported on 2021-07-21 near Ovando.
Colored swath = NOAA MRMS radar-estimated hail size; dots = NOAA SPC reports in Montana. Radar-indicated, not a guarantee of damage.
The last hail here fell on 2023-05-22, around Helmville. A free SwathIQ account -- hand-reviewed, invite within 24-48h -- pulls Powell 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 14 separate hail days here since 2010 -- 0.8 a year over 17 years of record. They carry 17 reports in total: most hail days here are logged from a single spot. 6 of those 17 years produced none at all. The busiest single year was 2019, with 2 hail days. The last five years have been quieter than the long run: 2 days since 2022, against 1.0 a year before that.
No stone of 2 inches or more has ever been reported in Powell County: all 14 hail days on record topped out below that. Golf-ball size is rarer still: 1.75 inches or more on 1 of the 14 days.
Across the whole of Montana, see the Montana hail map and history.
Reports cluster nearest Helmville -- 3 of the county's 14 hail days -- then Deer Lodge (3), Ovando (2) and Avon (2).
| Place | Hail days since 2010 | Largest stone |
|---|---|---|
| 4 Wnw Ovando | 1 | 1.75″ |
| 1 Ese Elliston | 1 | 1.50″ |
| 4 Se Helmville | 1 | 1.50″ |
| 6 N Avon | 1 | 1.50″ |
| 6 Nne Avon | 1 | 1.50″ |
The season runs May through July: 13 of the 14 hail days on record fall in those 3 months (93%). July is the single busiest month, with 9 of them (64%). That peak closes the window: the season builds all the way to its worst month and then stops. Hail has also been reported in August, outside that window. Reports span 4 of the 12 calendar months; the other 8 have never produced one.
| Month | Hail days |
|---|---|
| May | 2 |
| June | 2 |
| July | 9 |
| August | 1 |
That day put 1 report on the map, the biggest 1 inch near Helmville. No hail day has been reported here yet this year.
| Date | Max hail | Reports |
|---|---|---|
| 2023-05-22 | 1.00″ | 1 |
| 2022-07-08 | 1.50″ | 1 |
| 2021-07-21 | 1.75″ | 2 |
| 2019-07-14 | 1.50″ | 1 |
| 2019-07-13 | 1.25″ | 1 |
| 2018-07-27 | 1.25″ | 1 |
| 2017-05-06 | 1.00″ | 1 |
| 2016-07-17 | 1.00″ | 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 1.75 inches, which is the red band. Look up a street address with the hail history by address tool.
The nearest counties with a page of their own: Lewis and Clark County (22 hail days), Missoula County (22) and Jefferson County (18). Every one of them takes more hail than Powell County.
Lewis and Clark County · Missoula County · Jefferson County
Back to the Montana hail map or the U.S. hail map.
Data & method: NOAA/NWS Storm Prediction Center reports + NOAA MRMS MESH radar, Powell County, Montana only. Radar-indicated and observation-based -- informational only, not a guarantee of damage or a valid claim.