NOAA Storm Events Data
Iowa Hail Statistics: 10 Years of Storm Data (2026)
Every number on this page is computed from the NOAA NCEI Storm Events database, 2015 to 2025, filtered to Iowa hail and thunderstorm wind events. No estimates, no industry guesses. Free to cite with attribution.
Last updated: June 12, 2026
3,736
hail events in Iowa, 2015 to 2025
339.6
hail events per year on average
Polk
county with the most hail events (171)
June
peak hail month (929 events)
Hail and Storm Wind Events Per Year
Statewide event counts from NCEI Storm Events records, plus property damage where it was recorded in the per-event fields. Those fields undercount catastrophic events like the 2020 derecho; see the methodology notes below.
| Year | Hail events | Thunderstorm wind events | Reported property damage |
|---|---|---|---|
| 2015 | 350 | 342 | $10.7 million |
| 2016 | 207 | 413 | $12.1 million |
| 2017 | 589 | 637 | $5.0 million |
| 2018 | 376 | 473 | $5.0 million |
| 2019 | 232 | 414 | $3.2 million |
| 2020 | 287 | 429 | $324K |
| 2021 | 198 | 381 | $3.7 million |
| 2022 | 247 | 322 | $1.4 million |
| 2023 | 577 | 294 | $671K |
| 2024 | 417 | 659 | $1.8 million |
| 2025 | 256 | 564 | $939K |
Top Iowa Counties by Hail Events
Counties ranked by recorded hail events, 2015 to 2025. Des Moines metro counties are marked.
| Rank | County | Hail events |
|---|---|---|
| 1 | Polk (Des Moines metro) | 171 |
| 2 | Linn | 141 |
| 3 | Story (Des Moines metro) | 128 |
| 4 | Scott | 120 |
| 5 | Warren (Des Moines metro) | 97 |
| 6 | Johnson | 74 |
| 7 | Marion | 71 |
| 8 | Guthrie | 70 |
| 9 | Pottawattamie | 68 |
| 10 | Benton | 66 |
| 11 | Plymouth | 66 |
| 12 | Black Hawk | 59 |
| 13 | Cerro Gordo | 59 |
| 14 | Dickinson | 58 |
| 15 | Woodbury | 58 |
Metro county hail event counts, 2015 to 2025: Polk 171, Story 128, Warren 97, Dallas 57, Jasper 57, Madison 30.
Iowa Hail Season, Month by Month
Hail events by month across all 11 years. This is what people mean when they say Iowa hail season.
| Month | Hail events (2015 to 2025) | Share of all hail |
|---|---|---|
| January | 1 | 0.0% |
| February | 37 | 1.0% |
| March | 268 | 7.2% |
| April | 800 | 21.4% |
| May | 688 | 18.4% |
| June | 929 | 24.9% |
| July | 420 | 11.2% |
| August | 280 | 7.5% |
| September | 230 | 6.2% |
| October | 66 | 1.8% |
| November | 14 | 0.4% |
| December | 3 | 0.1% |
Largest Recorded Hail in Des Moines Metro Counties
The biggest hail size recorded in each metro county in NCEI Storm Events data, 2015 to 2025. For reference: a quarter is 1.00 inch, a golf ball is 1.75 inches, a baseball is 2.75 inches.
| County | Largest recorded hail | Date |
|---|---|---|
| Polk | 3.25 in | Jul 9, 2021 |
| Dallas | 3.00 in | Jul 9, 2021 |
| Warren | 3.00 in | May 14, 2020 |
| Jasper | 2.75 in | May 7, 2023 |
| Madison | 2.75 in | Jun 25, 2024 |
| Story | 2.50 in | Jul 11, 2020 |
Case Study: The August 10, 2020 Derecho
The derecho that crossed Iowa on August 10, 2020 is the single worst storm day in this dataset. NCEI records show 140 separate thunderstorm wind events in Iowa on that one day, with a maximum recorded gust of 126 knots, about 145 mph. Many Des Moines roofs that went through the derecho still shed shingles in ordinary windstorms today, because a shingle sealant strip that breaks once never fully reseals.
One honest note on dollars: the per-event damage fields in this dataset capture only a small fraction of derecho losses, which is why the 2020 row in the table above looks modest. NOAA accounts for catastrophic-event totals separately from these per-event records. For roof risk, the number that matters here is 140 damaging wind events across the state in a single day.
Methodology and Source
All figures come from the NOAA NCEI Storm Events Database, the federal record of severe weather maintained by the National Centers for Environmental Information. We downloaded the StormEvents_details bulk CSV files for 2015 through 2025, filtered to STATE = IOWA and EVENT_TYPE of Hail or Thunderstorm Wind, and computed every table on this page from those records with a script we keep for reproducibility.
Notes on reading the data: an "event" is one NCEI-recorded occurrence in one county zone, so a single storm crossing five counties counts five times. Property damage is as recorded in the per-event damage fields, is not adjusted for inflation, and undercounts catastrophic events like the 2020 derecho, where most losses were accounted for outside those fields. Hail size is the largest reported magnitude per event, in inches. County counts use county-type zones only.
Cite this page. You are welcome to reuse the tables and figures here in articles, reports, and presentations. Credit Bakeris Roofing and link to this page. For the underlying raw records, cite NOAA NCEI directly.
Storm Hit Your Neighborhood?
We have inspected central Iowa roofs after every storm in this dataset since 1990. If hail or wind hit your area, get the roof checked and documented. The inspection is free.
More on storm work: storm damage repair and our Des Moines service area.