SwathIQ / Hail map / Tennessee / Williamson County

Williamson County, Tennessee Hail Map & History

The most recent reported hail day was 2025-11-07, 266 days ago. Williamson 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 2025-05-20 near Franklin.

34
hail days since 2010
7
days with 2″+ hail
0
hail days this year
3.00″
largest stone on record

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

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The last hail here fell on 2025-11-07, around College Grove. A free SwathIQ account -- hand-reviewed, invite within 24-48h -- pulls Williamson 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 Williamson County

NOAA's Storm Prediction Center has logged 34 separate hail days here since 2010 -- 2.0 a year over 17 years of record. Those days carry 107 separate reports between them, better than three on a typical one. Exactly one year since 2010 passed with no reported hail day at all. One year dominates the record: 2025 alone produced 7 of the 34 days. The last five years track the long-run rate, with 13 days since 2022.

7 of the 34 days reached 2 inches or more -- 21%, or about one hail day in 5, the last on 2025-05-20. Those big days do not follow the county's usual calendar: most of them fall in May, not March. 10 of the 34 days reached golf-ball size, 1.75 inches or bigger.

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

Hardest-hit places in Williamson County

Reports cluster nearest Franklin -- 19 of the county's 34 hail days -- then Brentwood (11), Fairview (9), Eagleville (4) and College Grove (4). That one town is named on 56% of them. Beyond those, NOAA names Nolensville and Spring Hill on more than one hail day apiece.

PlaceHail days since 2010Largest stone
Franklin71.50″
Brentwood61.25″
9 SE Fairview33.00″
Fairview32.00″
5 SSW Fairview31.75″

When it hails in Williamson County

The season runs March through July: 28 of the 34 hail days on record fall in those 5 months (82%). March is the single busiest month, with 8 of them (24%). That peak opens the window: the season starts at its worst and eases off from there. September and December are the only months that have never produced a reported hail day.

MonthHail days
January1
February1
March8
April5
May8
June4
July3
August1
October2
November1

Recent Williamson County hail days

That day put 1 report on the map, the biggest 1 inch near College Grove. No hail day has been reported here yet this year.

DateMax hailReports
2025-11-071.00″1
2025-05-203.00″25
2025-05-082.00″4
2025-04-031.50″2
2025-04-022.50″6
2025-03-302.00″5
2025-03-231.00″1
2024-05-263.00″11

How to read the Williamson 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 3 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: Davidson County (32 hail days), Maury County (16) and Rutherford County (33). Williamson County takes more hail than any of them.

Davidson County · Maury County · Rutherford County

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

FAQ

How often does it hail in Williamson County, Tennessee?
NOAA's Storm Prediction Center has logged 34 separate hail days here since 2010 -- 2.0 a year over 17 years of record.
When is hail season in Williamson County?
The season runs March through July: 28 of the 34 hail days on record fall in those 5 months (82%).
How big does hail get in Williamson County?
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 2025-05-20 near Franklin.
When was the last hail in Williamson County?
The most recent reported hail day was 2025-11-07, 266 days ago.
Is the Williamson 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, Williamson County, Tennessee only. Radar-indicated and observation-based -- informational only, not a guarantee of damage or a valid claim.