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Great Falls hail storm history

Cascade County·NOAA NCEI Storm Events Database·~75-day publication lag

Great Falls is located in the Missouri River valley of central Cascade County, where the Rocky Mountain Front transitions into the northern High Plains. This geographic position creates a complex convective environment where hail-producing storms develop along the foothills and track eastward across the county. As a result, Great Falls experiences documented hail events throughout the spring and summer months.

Events ≥1" (10yr)
72
Significant ≥1.5" (10yr)
26
Avg per year (10yr)
7.2
Largest recorded
3"
Most recent
Aug 1, 2025
Total records
75
NOAA storm history
events (10 yr)72
≥1.5" significant26
peak year (20)2022
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Hail activity in Great Falls peaks during June and July, with secondary risk extending through May and August. Storms that produce hail typically form along the Rocky Mountain Front and move across Cascade County, with the high elevation and semi-arid climate creating conditions favorable for severe convection during the transition seasons. While hail events are less frequent in this region than in eastern Montana, individual storms can still produce significant damage when they occur.

Annual frequency — last 10 years

2025
15
2024
3
2023
4
2022
20
2021
2
2020
4
2019
11
2018
no events
2017
6
2016
7
≥2.0" severe≥1.5" significant≥1.0" marginal

When hail hits — monthly pattern

Avg events per month · all years · NOAA data

Jan0
Feb0
Mar0
Apr0
May4
Jun34
Jul28
Aug9
Sep0
Oct0
Nov0
Dec0

All recorded hail events

Of 75 recorded events, 26 (35%) reached 1.5" or larger — the threshold for likely functional damage on standard asphalt shingles.

Aug 1, 20251"quarter

Public reported 1 inch hail. Time of report estimated via radar.

Jul 29, 20251"quarter

Facebook report of 1 inch hail in Tiger Butte.

Jul 28, 20251"quarter

Corrects previous hail report from 9 WNW Monarch. Facebook report of 1 inch hail in Tiger Butte.

Public report with image of quarter sized hail next to a quarter for reference.

Aug 19, 20241"quarter

Public reports quarter sized hail. Gusty winds were also observed, which blew around items at the re…

A photo submitted from the public showed estimated 2.5 inch hail, along with damage to a vehicle win…

Spotter reported quarter size hail in Belt.

Jul 29, 20231.75"golf ball

Reports on social media of vehicles in Wayne being dented from large hail.

Jun 6, 20231"quarter

Employee reported one inch hail on southeast side of Great Falls. Started off as small hail.

Pictures submitted of large hail (1 inch) in Black Eagle.

Video showing hail was taken in Sun River. Person who took the video reported up to quarter sized ha…

Report from mping.

Aug 20, 20201"quarter

Posted on Twitter.

Jun 25, 20201.5"ping pong ball

A lot of quarter to ping pong sized hail. Also, reports wind shredded pine trees and a lot of branch…

Public reports 1 inch diameter hail via mping.

Aug 22, 20191"quarter

A COOP observer reported quarter sized (1 inch in diameter) hail.

Trained spotter reported 1 inch sized hail at 1 W Sun Prairie.

Quarter size hail reported on the northwest side of Great falls.

Hail of 1 inch diameter measured on north side of runway at Malmstrom Air Force Base.

Storm started around 230 PM and lasted until 245 PM. Hail was mostly pea to penny size. The larger h…

Jun 13, 20171"quarter

Trained spotter reported quarter size hail.

Jun 4, 20171"quarter

Spotter reported quarter-sized hail.

Quarter size hail reported in the Big Bend/Fox Farm area of Great Falls.

Hail reported 8 miles SE of Ulm.

A thunderstorm dropped 1 inch diameter hail at Belt 10WNW and at Belt 7NW.

Aug 10, 20161"quarter

A thunderstorm dropped 1 inch diameter hail near Benefis East in Great Falls. Also, a 1.75 inch diam…

Jun 11, 20161.5"ping pong ball

A thunderstorm dropped 1.5 inch diameter hail in Great Falls. The storm produced reports of hail ran…

A severe thunderstorm dropped 1.75 inch diameter hail at Highwood 10SE and 2 inch diameter hail at H…

Data source

NOAA National Centers for Environmental Information Storm Events Database. Publication lag is approximately 75 days — current-year events may be incomplete.

NOAA Storm Events Database ↗