SwathIQ / Hail map / Michigan / St. Clair County

St. Clair County, Michigan Hail Map & History

St. Clair County was hit as recently as 2026-09-02, 12 days ago. St. Clair County is hit in about half the years on record. The largest stone on record here is 2 inches, a hen egg and twice the National Weather Service's 1 inch severe criterion, reported on 2026-09-02 near Capac.

14
hail days since 2010
1
days with 2″+ hail
3
hail days this year
2.00″
largest stone on record

Colored swath = NOAA MRMS radar-estimated hail size; dots = NOAA SPC reports in Michigan. Radar-indicated, not a guarantee of damage.

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The last hail here fell on 2026-09-02, around Capac. 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.

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How often it hails in St. Clair County

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 19 reports in total: most hail days here are logged from a single spot. 8 of those 17 years produced none at all. One year dominates the record: 2026 alone produced 3 of the 14 days. The last five years have run hotter than the long-run rate: 6 days since 2022, against 0.7 a year before that.

Most hail here stays under 2 inches: only 1 of the 14 days on record passed it, 7%, the last on 2026-09-02. Those big days do not follow the county's usual calendar: most of them fall in September, not July. 5 of the 14 days reached golf-ball size, 1.75 inches or bigger.

Across the whole of Michigan, see the Michigan hail map and history.

Hardest-hit places in St. Clair County

Reports cluster nearest Capac -- 2 of the county's 14 hail days -- then Marysville (2), St. Clair (2) and Port Huron (2).

PlaceHail days since 2010Largest stone
1 NW Capac12.00″
Algonac11.75″
Capac11.75″
Emmett11.75″
Marysville11.75″

When it hails in St. Clair County

The season runs April through September: 13 of the 14 hail days on record fall in those 6 months (93%). July is the single busiest month, with 4 of them (29%). That peak sits inside the window rather than at either end. Hail has also been reported in February, outside that window. Reports span 7 of the 12 calendar months; the other 5 have never produced one.

MonthHail days
February1
April2
May1
June1
July4
August3
September2

Recent St. Clair County hail days

That day put 2 reports on the map, the biggest 2 inches near Capac. 3 hail days have already been reported this year.

DateMax hailReports
2026-09-022.00″2
2026-06-251.75″3
2026-02-181.25″1
2024-08-301.50″1
2023-07-201.75″1
2023-07-141.00″1
2020-08-151.00″1
2020-04-071.00″3

How to read the St. Clair County map

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 2 inches, which is the purple band. Look up a street address with the hail history by address tool.

Nearby counties

The nearest counties with a page of their own: Macomb County (24 hail days), Oakland County (28) and Genesee County (15). Every one of them takes more hail than St. Clair County.

Macomb County · Oakland County · Genesee County

Back to the Michigan hail map or the U.S. hail map.

FAQ

How often does it hail in St. Clair County, Michigan?
NOAA's Storm Prediction Center has logged 14 separate hail days here since 2010 -- 0.8 a year over 17 years of record.
When is hail season in St. Clair County?
The season runs April through September: 13 of the 14 hail days on record fall in those 6 months (93%).
How big does hail get in St. Clair County?
The largest stone on record here is 2 inches, a hen egg and twice the National Weather Service's 1 inch severe criterion, reported on 2026-09-02 near Capac.
When was the last hail in St. Clair County?
St. Clair County was hit as recently as 2026-09-02, 12 days ago.
Is the St. Clair County hail map free?
Yes, no login. A free account adds door-knock address lists and CRM exports.

Data & method: NOAA/NWS Storm Prediction Center reports + NOAA MRMS MESH radar, St. Clair County, Michigan only. Radar-indicated and observation-based -- informational only, not a guarantee of damage or a valid claim.