SwathIQ / Hail map / Missouri / Mercer County

Mercer County, Missouri Hail Map & History

Mercer County was hit as recently as 2026-06-10, 51 days ago. Mercer County is hit in about half the years on record. The largest stone on record here is 2.75 inches, a baseball and 2.8 times the National Weather Service's 1 inch severe criterion, reported on 2018-05-19 near Modena.

14
hail days since 2010
2
days with 2″+ hail
4
hail days this year
2.75″
largest stone on record

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

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The last hail here fell on 2026-06-10, around Princeton. A free SwathIQ account -- hand-reviewed, invite within 24-48h -- pulls Mercer 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 Mercer 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 25 reports in total: most hail days here are logged from a single spot. 9 of those 17 years produced none at all. One year dominates the record: 2026 alone produced 4 of the 14 days. The last five years have run hotter than the long-run rate: 7 days since 2022, against 0.6 a year before that.

2 of the 14 days reached 2 inches or more -- 14%, or about one hail day in 7, the last on 2024-05-26. Those big days do not follow the county's usual calendar: most of them fall in May, not June. More than half of every hail day on record here -- 9 of 14 -- reached golf-ball size, 1.75 inches or bigger.

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

Hardest-hit places in Mercer County

Reports cluster nearest Mercer -- 7 of the county's 14 hail days -- then Princeton (5) and Mill Grove (2). That one town is named on 50% of them.

PlaceHail days since 2010Largest stone
Mercer51.75″
Princeton51.75″
2 N Modena12.75″
2 Ene Mill Grove12.00″
5 SE Mercer12.00″

When it hails in Mercer County

The season runs March through June: 12 of the 14 hail days on record fall in those 4 months (86%). June is the single busiest month, with 5 of them (36%). That peak closes the window: the season builds all the way to its worst month and then stops. Hail has also been reported in July and August, outside that window. Reports span 6 of the 12 calendar months; the other 6 have never produced one.

MonthHail days
March1
April3
May3
June5
July1
August1

Recent Mercer County hail days

That day put 4 reports on the map, the biggest 1.75 inches near Princeton. 4 hail days have already been reported this year.

DateMax hailReports
2026-06-101.75″4
2026-04-171.75″1
2026-04-151.00″1
2026-04-021.75″1
2024-05-262.00″3
2023-03-311.75″3
2022-05-171.00″1
2021-06-201.75″2

How to read the Mercer 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 2.75 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, over the state line included: Grundy County (33 hail days), Harrison County (31), Sullivan County (21) and Decatur County, Iowa (15). Every one of them takes more hail than Mercer County.

Grundy County · Harrison County · Sullivan County · Decatur County, Iowa

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

FAQ

How often does it hail in Mercer County, Missouri?
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 Mercer County?
The season runs March through June: 12 of the 14 hail days on record fall in those 4 months (86%).
How big does hail get in Mercer County?
The largest stone on record here is 2.75 inches, a baseball and 2.8 times the National Weather Service's 1 inch severe criterion, reported on 2018-05-19 near Modena.
When was the last hail in Mercer County?
Mercer County was hit as recently as 2026-06-10, 51 days ago.
Is the Mercer 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, Mercer County, Missouri only. Radar-indicated and observation-based -- informational only, not a guarantee of damage or a valid claim.