The most recent reported hail day was 2026-04-26, 96 days ago. St. Clair 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 2012-04-28 near Belleville.
Colored swath = NOAA MRMS radar-estimated hail size; dots = NOAA SPC reports in Illinois. Radar-indicated, not a guarantee of damage.
The last hail here fell on 2026-04-26, around Belleville. A free SwathIQ account -- hand-reviewed, invite within 24-48h -- pulls St. Clair 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 47 separate hail days here since 2010 -- 2.8 a year over 17 years of record. Those days carry 151 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 2012, with 7 hail days. The last five years track the long-run rate, with 13 days since 2022.
Most hail here stays under 2 inches: only 3 of the 47 days on record passed it, 6%, the last on 2023-07-17. Those big days do not follow the county's usual calendar: most of them fall in April, not May. 13 of the 47 days reached golf-ball size, 1.75 inches or bigger.
Across the whole of Illinois, see the Illinois hail map and history.
Reports cluster nearest Belleville -- 9 of the county's 47 hail days -- then O'Fallon (9), Caseyville (8), Shiloh (8) and Millstadt (8). Beyond those, NOAA names Fairview Heights, Mascoutah, Freeburg, New Athens, Cahokia, Swansea, Fairmont City, Marissa and Lebanon on more than one hail day apiece.
| Place | Hail days since 2010 | Largest stone |
|---|---|---|
| Caseyville | 7 | 1.75″ |
| O'Fallon | 6 | 2.75″ |
| Belleville | 5 | 3.00″ |
| Mascoutah | 5 | 1.75″ |
| 2 W Belleville | 4 | 2.00″ |
The season runs March through July: 41 of the 47 hail days on record fall in those 5 months (87%). May is the single busiest month, with 13 of them (28%). That peak sits inside the window rather than at either end. October are the only months that have never produced a reported hail day.
| Month | Hail days |
|---|---|
| January | 1 |
| February | 1 |
| March | 5 |
| April | 10 |
| May | 13 |
| June | 6 |
| July | 7 |
| August | 1 |
| September | 1 |
| November | 1 |
| December | 1 |
That day put 1 report on the map, the biggest 1 inch near Belleville. 1 hail day has already been reported this year.
| Date | Max hail | Reports |
|---|---|---|
| 2026-04-26 | 1.00″ | 1 |
| 2025-04-02 | 1.75″ | 2 |
| 2025-03-30 | 1.50″ | 4 |
| 2025-03-14 | 1.75″ | 9 |
| 2024-05-26 | 1.75″ | 9 |
| 2024-05-08 | 1.00″ | 3 |
| 2024-03-14 | 1.75″ | 7 |
| 2023-07-17 | 2.50″ | 8 |
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: Monroe County (24 hail days), Madison County (54), Clinton County (15) and St. Louis City, Missouri (26). St. Clair County sits in between.
Monroe County · Madison County · Clinton County · St. Louis City, Missouri
Back to the Illinois hail map or the U.S. hail map.
Data & method: NOAA/NWS Storm Prediction Center reports + NOAA MRMS MESH radar, St. Clair County, Illinois only. Radar-indicated and observation-based -- informational only, not a guarantee of damage or a valid claim.