The May 26, 2010 Denver hailstorm hit the northeast metro at midday: between about 1:20 and 2:10 p.m., NOAA logged golf ball to baseball hail across Commerce City, Thornton, Northglenn, Brighton and the Barr Lake area, with 2.75-inch stones the largest. Hail piled up to a foot deep on roads, and the Rocky Mountain Insurance Information Association estimated about 13,600 auto and homeowner claims and $70 million in damage.
What happened on May 26, 2010
NWS Boulder’s summary describes severe thunderstorms that “pounded parts of the Urban Corridor and Northeast Plains with very large hail, damaging wind and tornadoes,” hitting northeast Denver, Brighton and Commerce City hardest before moving on toward Hudson, Prospect Valley, Byers and Deer Trail. Wind and hail stripped bark and branches from trees. Two tornadoes touched down in open country, one near Denver International Airport and one near Keenesburg, and lightning struck a child in Commerce City.
The first reports came at about 1:20 p.m. near Hazeltine, north of Commerce City, with 2-inch hail. Over the next 30 minutes the hail spread across Commerce City, Welby, Thornton and Northglenn, and at about 1:51 p.m. the largest stones, 2.75 inches, fell north and south-southwest of Barr Lake. The Storm Prediction Center log notes window damage with 2-inch hail in Commerce City. A second, weaker round in the evening brought 0.75 to 1.5 inch hail to Broomfield, Henderson and Lafayette.
Where the hail fell
| Area | Largest hail on record | Size name |
|---|---|---|
| Barr Lake and south of Brighton | 2.75 in. | Baseball |
| Commerce City and Hazeltine | 2.00 in. | Hen egg |
| Thornton | 1.75 in. | Golf ball |
| Northglenn | 1.75 in. | Golf ball |
| Lafayette (evening) | 1.50 in. | Ping pong ball |
| Near Denver International Airport | 1.25 in. | Half dollar |
| Welby and Brighton | 1.00 in. | Quarter |
If you live in Commerce City, Thornton or Henderson, you were in or near the core of this storm, and the same area was hit again by the May 30, 2024 storm.
What deep, golf ball to baseball hail does to a roof
Two things set this storm apart. The size, up to 2.75 inches, is large enough to fracture shingles and crack tile on any slope it hits squarely. And the volume, enough to drift a foot deep on roads, means hail sat on roofs, packed into valleys and filled gutters. Melting hail that cannot drain can back water up under the shingle edges and leak at the eaves even where the shingles themselves held up. Gutters loaded with ice can also pull away from the fascia.
Homes built at the same time in the same subdivision often have the same roofing, so damage on one house is a strong hint for the houses around it. That is not proof for your roof, but it is a reason to look.
How to check a roof for this storm
- Find out whether your roof has been replaced since May 2010. If it has, this storm is history for your house.
- Look along the eaves and inside soffits for old water stains, a sign of meltwater backing up after a heavy hail.
- Check gutters for bent hangers or sections pulled away from the fascia.
- Book an inspection and ask the inspector to separate old, weathered hail marks from newer ones.
Claim timing for a Colorado storm
Colorado sets no single deadline to report roof damage; your policy does, often as prompt notice. A Colorado homeowner's policy cannot give you less time to sue than the statute of limitations (C.R.S. 10-4-110.8(12)), and the Division of Insurance advises calling your insurer or agent soon after a hailstorm. Replacement cost policies usually hold back depreciation until the work is done: see finishing repairs to recover depreciation and how long you have to file a hail claim.
This storm is now 16 years old, and hail marks weather. An inspection shows whether marks look fresh or aged, which an adjuster weighs when tying damage to a date. General information, not legal advice; the claim is always yours, and our part is the inspection, dated photos and written scope.
Denver, CO inspection and hail help
If you live in the Denver metro, start with our Denver hail damage repair page, book a free Denver roof inspection, or read what a Denver roof inspection covers. Integrity Roofing and Painting is veteran-owned and family-run since 1990, an Owens Corning Platinum Preferred contractor with 650+ Google reviews, and we respond the same business day. Call (303) 209-0152.
Other recorded storms in the Denver metro
- May 30, 2024 Hailstorm: hail to 2.75 in.
- June 21 and 22, 2023 Hailstorms: hail to 2.5 in.
- June 6, 2020 Derecho: gusts to 81 mph
- June 18 and 19, 2018 Hailstorms: hail to 3 in.
- May 8, 2017 Denver hailstorm (full write-up)
- September 29, 2014 Hailstorm: hail to 1.75 in.
- June 6, 2012 hailstorm, Colorado Springs and south Denver (full write-up)
- July 13, 2011 Hailstorm: hail to 4.5 in.
- Full storm archive: Colorado Springs, Denver and Austin
Sources: NOAA SPC storm reports, May 26, 2010; NOAA NCEI Storm Events Database, event 224718 (Barr Lake, $70 million); NOAA NCEI Storm Events Database, event 224717 (Barr Lake, 2.75 in.); NWS hail size reference; C.R.S. 10-4-110.8 (unofficial reproduction); Colorado Division of Insurance, hail consumer advisory (May 22, 2024).
