Skip to content
HailIndex

Ames hail storm history

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

Story County, home to Ames, has recorded only one documented hail event of 1 inch or larger in the past decade according to NOAA data. The largest hailstone on record in Ames measured 0.75 inches in diameter. Despite this relatively low historical frequency, Ames sits within central Iowa's active hail corridor, where atmospheric conditions regularly favor severe thunderstorm development.

Events ≥1" (10yr)
176
Significant ≥1.5"
59
Avg per year
17.6
Largest recorded
3"
Most recent
Jun 20, 2025
Total records
217
NOAA storm history
events (10 yr)171
≥1.5" significant59
peak year (47)2023

Hail in the Ames area peaks during May and June, with secondary activity in April and July. These months align with the interaction of the dryline and Gulf moisture patterns that create favorable conditions for large-hail supercells across central Iowa. The Des Moines corridor, which includes the Ames region, ranks among the most active hail corridors in the state.

Annual frequency — last 10 years

2025
18
2024
19
2023
55
2022
6
2021
13
2020
17
2019
15
2018
52
2017
16
≥2.0" severe≥1.5" significant≥1.0" marginal

When hail hits — monthly pattern

Avg events per month · all years · NOAA data

Jan0
Feb0
Mar27
Apr32
May72
Jun31
Jul33
Aug11
Sep10
Oct1
Nov0
Dec0

All recorded hail events

Of 217 recorded events, 59 (27%) reached 1.5" or larger — the threshold for likely functional damage on standard asphalt shingles.

Jun 20, 20250.75"penny

Report via mping.

Mostly small hail with a few stones up to quarter sized.

Report relayed by broadcast media. Time estimated by radar.

Trained spotter report of 0.88 inch hail near Ames.

Reported from mping.

Jul 30, 20241"quarter

Delayed report, time estimated by radar.

Jul 15, 20241"quarter

Report of nickel to quarter sized hail.

Jul 7, 20241"quarter

MPING report of 1-inch hail. Time of occurrence estimated from radar.

Jun 4, 20241"quarter

Report via Raccoon Valley Radio. Time of occurrence estimated from radar.

Social media report between Cambridge and Nevada.

Dispatch relayed a report of quarter sized hail in Ogden reported by police.

Variety of hail with largest up to quarter sized.

Penny sized hail mixed with pea hail.

Jun 4, 20230.88"penny

Nickel sized hail and winds estimated near 45 mph.

Image received via twitter.

Emergency manager relayed report of silver dollar sized hail.

Reported on social media.

Report via social media.

Received via email, time estimated by radar.

Sep 18, 20221"quarter

Report of corn stripped due to hail. Delayed report. Time estimated via radar.

Golf ball sized hail ongoing at time of report.

Jun 15, 20221"quarter

Report via social media from the interstate 35 rest area. Time estimated by radar.

Delayed report of two to three inch hail. Time estimated by radar.

Aug 24, 20210.88"penny

Trained spotter reported nickel sized hail and sustained 30 mph winds.

Report via mping app.

Oct 22, 20200.88"penny

A trained spotter relayed an image of roughly penny to nickel sized hail.

Jul 14, 20201"quarter

A trained spotter reported quarter sixed hail north of Boone.

A trained spotter reported quarter sized hail at the intersection of E18 and R38 northwest of Gilber…

Public reported penny sized hail, via the mPING app.

Aug 29, 20191"quarter

WHO TV relayed public report of quarter sized hail.

Jul 17, 20190.75"penny

Trained spotter reported penny sized hail.

Jun 15, 20190.88"penny

Public reported nickel sized hail.

Emergency manager reported ping pong ball sized hail.

Apr 17, 20191"quarter

Trained spotter reported quarter inch hail.

Sep 2, 20180.88"penny

Public reported nickel sized hail.

Aug 28, 20181"quarter

Trained spotter reported 3 minutes of dime to quarter sized hail.

A retired NWS employee reported quarter sized hail. This is a delayed report.

Aug 1, 20181"quarter

Public reported quarter sized hail. This is a delayed report.

Jul 26, 20180.75"penny

Public reported nickel sized hail. This is a delayed report.

Jun 14, 20181"quarter

Public reported quarter sized hail.

Trained spotter reported ping pong ball sized hail.

May 29, 20180.88"penny

Public reported nickel sized hail.

Trained spotter reported quarter sized hail falling on the south side of Maxwell along with strong w…

Public relayed a picture of half dollar to ping pong ball sized hail on the north side of Ames. The …

Trained spotter reported up to about ping pong ball sized hail.

Apr 14, 20180.88"penny

Public reported pea to nickel sized hail in Stratford.

Aug 14, 20171"quarter

Trained spotter reported brief pea to quarter sized hail between Nevada and Colo on Highway 30.

Emergency manager reported nickel to quarter sized hail along with estimated 40-45 mph wind gusts.

Jun 19, 20170.75"penny
Jun 17, 20171"quarter

Coop observer reported quarter sized hail. This is a delayed report and time estimated from radar.

Storm chaser reported penny sized hail.

Coop observer reported up to ping pong ball sized hail covering the ground in west Jewell. Time est…

Apr 20, 20170.88"penny

Public reported up to nickel sized hail.

Apr 15, 20170.75"penny

Amateur radio operator reported penny sized hail.

Public reported ground covered with nickel sized hail.

Public reported up to quarter sized hail.

About this data

The low frequency of significant hail events in Ames reflects both local storm patterns and NOAA's reporting standards. Story County's single documented 1-inch-or-larger event over ten years suggests either that large hail is genuinely infrequent in this specific area, or that storm reports in less populated regions may be underreported. 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