SwathIQ / Hail map / Iowa / Union County

Union County, Iowa Hail Map & History

Union County was hit as recently as 2026-06-10, 51 days ago. Union County has recorded hail in nearly every year on the archive. 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 2021-06-18 near Lorimor.

30
hail days since 2010
5
days with 2″+ hail
1
hail days this year
3.00″
largest stone on record

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

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The last hail here fell on 2026-06-10, around Creston. A free SwathIQ account -- hand-reviewed, invite within 24-48h -- pulls Union 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 Union County

NOAA's Storm Prediction Center has logged 30 separate hail days here since 2010 -- 1.8 a year over 17 years of record. Those days carry 56 separate reports between them, two or three on a typical one. 2 of those 17 years produced none at all. The busiest single year was 2011, with 4 hail days. The last five years track the long-run rate, with 9 days since 2022.

5 of the 30 days reached 2 inches or more -- 17%, or about one hail day in 6, the last on 2022-03-05. They land in the same month as everything else, June. 12 of the 30 days reached golf-ball size, 1.75 inches or bigger.

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

Hardest-hit places in Union County

Reports cluster nearest Creston -- 16 of the county's 30 hail days -- then Lorimor (5), Afton (5), Creston Airport (4) and Cromwell (4). That one town is named on 53% of them. Beyond those, NOAA names Ne Arispe and Arispe on more than one hail day apiece.

PlaceHail days since 2010Largest stone
Creston81.75″
Afton41.00″
Lorimor33.00″
Ne Arispe31.75″
3 E Creston22.00″

When it hails in Union County

The season runs April through June: 25 of the 30 hail days on record fall in those 3 months (83%). June is the single busiest month, with 14 of them (47%). That peak closes the window: the season builds all the way to its worst month and then stops. Reports span 8 of the 12 calendar months; the other 4 have never produced one.

MonthHail days
February1
March1
April4
May7
June14
July1
August1
September1

Recent Union County hail days

That day put 2 reports on the map, the biggest 1 inch near Creston. 1 hail day has already been reported this year.

DateMax hailReports
2026-06-101.00″2
2025-04-171.00″3
2024-05-211.25″1
2024-04-301.75″7
2023-07-171.00″1
2023-06-171.00″2
2023-05-071.00″1
2022-09-171.75″3

How to read the Union 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: Adair County (28 hail days), Adams County (20) and Ringgold County (21). Union County takes more hail than any of them.

Adair County · Adams County · Ringgold County

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

FAQ

How often does it hail in Union County, Iowa?
NOAA's Storm Prediction Center has logged 30 separate hail days here since 2010 -- 1.8 a year over 17 years of record.
When is hail season in Union County?
The season runs April through June: 25 of the 30 hail days on record fall in those 3 months (83%).
How big does hail get in Union 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 2021-06-18 near Lorimor.
When was the last hail in Union County?
Union County was hit as recently as 2026-06-10, 51 days ago.
Is the Union 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, Union County, Iowa only. Radar-indicated and observation-based -- informational only, not a guarantee of damage or a valid claim.