Iowa and Illinois derecho and hail country
Des Moines Storm Damage: Iowa's Hail Leader and the Contractors Who Fix It
Polk County logs more 1-inch hail than any other county in Iowa, and the Des Moines metro also sat inside the 2020 derecho's strongest-wind corridor. This page covers the record for Des Moines, West Des Moines and Ankeny, and the trades that handle each kind of damage.
Iowa's most hail-struck county
NOAA's Storm Events Database records 127 hail events of 1 inch or larger in Polk County from 2016 through 2025, the most of any Iowa county; Story County is second with 98 (NCEI). In Polk, 34 of those events reached 1.75 inches and 17 reached 2 inches, and the 1-inch hail fell on 27 separate days.
The biggest stones of the decade: a photo shared on social media documented 3.25-inch hail in Beaverdale on July 9, 2021, and WOI-5 reported 3-inch hail at its West Des Moines station on August 19, 2022.
Tornadoes through the metro
Polk County's tornado property damage in NCEI's 2016-2025 file totals more than $82 million, most of it from three EF2s.
- March 5, 2022: an EF2 crossed from Warren County near Highway 69 and County Line Road, took the roof off a house on E Pine Avenue and hit the Woodland Hills neighborhood. NCEI lists $75 million in property damage.
- April 26, 2024: an EF2 formed on the east side near Easter Lake, moving from tree and fence damage to roof damage as it tracked northeast.
- May 21, 2024: a long-track EF2 began near Johnston High School, damaging fascia and soffits on nearby houses, blowing out the school's windows and leaving minor roof damage along its path, with two injuries.
FEMA's DR-4779 covers the April 2024 storms and tornadoes and DR-4784 covers the May 2024 storms, tornadoes and flooding; Polk County is designated in both. The county's newest declaration, DR-4942, was issued on September 1, 2026, for severe storms and flooding that began July 1, 2026.
The derecho in Polk County
NOAA's database holds 22 separate thunderstorm wind entries for Polk County on August 10, 2020. The strongest measured gust was 74 knots at an Elkhart mesonet station, about 85 mph, and the Des Moines airport sensor recorded 65 knots. The SPC report log adds an 85 mph personal weather station reading west of Urbandale and roof damage in Urbandale.
The episode summary attached to those entries estimates at least 850,000 acres of partial or complete crop loss, more than 1.4 million customers without power at the peak across the affected states, and early losses above $7.5 billion. NWS Des Moines placed the metro inside the strongest-wind zone between Highway 30 and Interstate 80.
Hail damage, sorted by trade
| Damage after a Polk County hailstorm | Who fixes it | Iowa credential to check |
|---|---|---|
| Bruised or cracked shingles, split vents | Roofing contractor | DIAL contractor registration |
| Cracked vinyl or dented aluminum siding | Siding contractor | DIAL contractor registration |
| Broken glass, torn screens, dented frames | Window contractor or glazier | DIAL contractor registration |
| Crushed gutters and downspouts | Gutter installer | DIAL contractor registration |
| Flattened condenser fins | HVAC contractor | Plumbing and Mechanical Systems Board license |
That last row matters: DIAL says any business providing plumbing, mechanical, HVAC, refrigeration or sheet metal services must be licensed through the Plumbing and Mechanical Systems Board, which issues the license and registration number together. In that licensing law, "sheet metal" is defined as heating, ventilation, air-conditioning, pollution control and fume hood systems and their ducts (Iowa Code 105.2). Everyone else on a hail job needs the standard registration once they earn $2,000 a year from construction.
If the roof is replaced, the National Roofing Directory's explainer on Class 4 impact-resistant shingles covers what that rating tests. For Iowa's state requirements in one place, see its Iowa roofing licensing page.
Find roofers in Des Moines, West Des Moines and Ankeny on the National Roofing Directory; the companies below are its listings for those three cities.
Frequently asked questions
Which Iowa county gets the most large hail?
Polk County. NOAA's Storm Events Database records 127 hail events of 1 inch or larger there from 2016 through 2025, ahead of Story County's 98. The figure counts reported events, so it reflects hail that was observed and logged.
Is there a current FEMA declaration covering Polk County?
FEMA issued DR-4942 on September 1, 2026, for severe storms and flooding that began July 1, 2026, and Polk County is one of its designated areas. Check the declaration page for the programs available.
Who repairs a hail-damaged air conditioner in Iowa?
An HVAC contractor licensed through Iowa's Plumbing and Mechanical Systems Board. DIAL routes HVAC businesses to that board's license rather than the standard registration, so ask the HVAC company for its board license number.
Sources
- 1-inch hail — ncei.noaa.gov
- strongest-wind corridor — weather.gov
- 3.25-inch hail in Beaverdale on July 9, 2021 — ncei.noaa.gov
- 3-inch hail at its West Des Moines station on August 19, 2022 — ncei.noaa.gov
- EF2 crossed from Warren County — ncei.noaa.gov
- EF2 formed on the east side — ncei.noaa.gov
- EF2 began near Johnston High School — ncei.noaa.gov
- DR-4779 — fema.gov
- DR-4784 — fema.gov
- DR-4942 — fema.gov
- 74 knots at an Elkhart mesonet station — ncei.noaa.gov
- Des Moines airport sensor recorded 65 knots — ncei.noaa.gov
- SPC report log — spc.noaa.gov
- DIAL — dial.iowa.gov
- Iowa Code 105.2 — legis.iowa.gov