The storms also spawned tornadoes. AccuWeather.com reported at least seven were reported along the Front Range, including a weak one at Denver International Airport and one in Grover, Colo., that yanked a tree from the ground and dumped it 20 feet away.
The area also was pelted by hail, high winds and heavy rain. Some streets were closed by flooding for Thursday's morning rush hour.
The storm was at its worst around midnight. Division Chief Gary Armstrong said the West Metro Fire Protection District responded to 19 calls between 11:50 p.m. Wednesday and 12:30 a.m. Thursday.
"It was just crazy," he told the Denver Post.
In Jefferson County west of Denver, one house was hit by multiple fires, Armstrong said.
"Lightning hit the house and started electrical fires inside the walls," he said. "We were digging fires out of the walls."
The South Metro Fire District also responded to several calls.
In Jefferson County, five townhouses were flooded when water accumulated in window wells and broke the glass.
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