Mankato hail storm history
Blue Earth County·NOAA NCEI Storm Events Database·~75-day publication lag
Blue Earth County, where Mankato is located, has recorded 15 documented hail events of 1 inch or larger over the past 10 years. Mankato sits at the northern edge of the primary hail belt that extends across the central United States, placing it in a zone of moderate hail frequency compared to regions further south.
Hail in Mankato occurs most frequently during June and July, when afternoon thunderstorms develop along dry line boundaries and low-level jet streams. Secondary activity occurs in May and August. The largest recorded hail event in Blue Earth County was 2 inches in diameter, which causes severe damage to residential roofing across all shingle types.
Annual frequency — last 10 years
When hail hits — monthly pattern
Avg events per month · all years · NOAA data
All recorded hail events
Of 130 recorded events, 37 (28%) reached 1.5" or larger — the threshold for likely functional damage on standard asphalt shingles.
Report of hail covering the ground, with the largest stone being quarter-sized. Also tree branches d…
Quarter to golf ball sized hail.
Photo measurement provided via X.
A CoCoRaHS measured golfball size hail.
Nickel size hail just east of Madelia.
There was a social media picture of golf ball size hail in the western portion of Mankato.
Social media had a picture of 2 inch hail in northern Le Sueur County.
A local trained spotter reported dime to occasional quarter size hail in the town of Belle Plaine. R…
There was a large swath of very large hail, up to 2.5 inches in diameter, that fell from Lake Crysta…
There was a swath of large hail, which moved from Le Sueur, northeast to around Heidelberg.
In addition to the large hail stone, there was a power pole blown down in Waseca.
A fire department spotter reported hail as large as two inches fell for around 15 minutes at Lake Ha…
There were several reports of large hail, up to 2 inches in diameter, that fell from southwest of Sh…
Some minor crop damage also occurred with wind driven hail.
The 15 documented events ≥1 inch represent NOAA Storm Events Database records for Blue Earth County over a 10-year period. This count includes 6 significant events ≥1.5 inches capable of functional roof damage. Because Mankato is a smaller market, local hail event reporting may lag behind larger metropolitan areas, though NOAA's national database provides consistent methodology across all counties. Current-year data is excluded from the annual frequency table until October, when NOAA's Storm Events Database has processed the full hail season accounting for the standard 75-day reporting lag.
NOAA Storm Events Database source