The most recent reported hail day was 2026-04-28, 94 days ago. Delaware County is hit in most years. 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 2020-03-27 near Zena.
Colored swath = NOAA MRMS radar-estimated hail size; dots = NOAA SPC reports in Oklahoma. Radar-indicated, not a guarantee of damage.
The last hail here fell on 2026-04-28, around Kansas. A free SwathIQ account -- hand-reviewed, invite within 24-48h -- pulls Delaware 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 26 separate hail days here since 2010 -- 1.5 a year over 17 years of record. They carry 44 reports in total: most hail days here are logged from a single spot. 5 of those 17 years produced none at all. The busiest single year was 2017, with 4 hail days. The last five years track the long-run rate, with 7 days since 2022.
6 of the 26 days reached 2 inches or more -- 23%, or about one hail day in 4, the last on 2024-03-14. Those big days do not follow the county's usual calendar: most of them fall in March, not May. 9 of the 26 days reached golf-ball size, 1.75 inches or bigger.
Across the whole of Oklahoma, see the Oklahoma hail map and history.
Reports cluster nearest Grove -- 14 of the county's 26 hail days -- then Kansas (5), Jay (3), Afton (3) and Twin Oaks (2). That one town is named on 54% of them. Beyond those, NOAA names West Siloam Springs, Colcord and Oaks on more than one hail day apiece.
| Place | Hail days since 2010 | Largest stone |
|---|---|---|
| Grove | 4 | 2.50″ |
| 6 Ne Grove | 2 | 1.75″ |
| 5 Nw Grove | 2 | 1.50″ |
| 4 N Grove | 2 | 1.25″ |
| 2 N Zena | 1 | 3.00″ |
The season runs March through July: 22 of the 26 hail days on record fall in those 5 months (85%). May is the single busiest month, with 8 of them (31%). That peak sits inside the window rather than at either end. Hail has also been reported in August, September and October, outside that window. Reports span 7 of the 12 calendar months; the other 5 have never produced one.
| Month | Hail days |
|---|---|
| March | 5 |
| April | 7 |
| May | 8 |
| July | 2 |
| August | 1 |
| September | 1 |
| October | 2 |
That day put 1 report on the map, the biggest 1.75 inches near Kansas. 2 hail days have already been reported this year.
| Date | Max hail | Reports |
|---|---|---|
| 2026-04-28 | 1.75″ | 1 |
| 2026-04-25 | 1.00″ | 1 |
| 2025-05-18 | 1.00″ | 1 |
| 2024-05-26 | 1.75″ | 2 |
| 2024-05-08 | 1.25″ | 2 |
| 2024-03-14 | 2.00″ | 3 |
| 2022-05-14 | 1.50″ | 1 |
| 2020-07-11 | 1.75″ | 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, over the state line included: Ottawa County (32 hail days), Craig County (23), Mayes County (37) and McDonald County, Missouri (41). Delaware County sits in between.
Ottawa County · Craig County · Mayes County · McDonald County, Missouri
Back to the Oklahoma hail map or the U.S. hail map.
Data & method: NOAA/NWS Storm Prediction Center reports + NOAA MRMS MESH radar, Delaware County, Oklahoma only. Radar-indicated and observation-based -- informational only, not a guarantee of damage or a valid claim.