A rare, quarter-mile-wide tornado cut a swath across mainly open country in southeastern Wyoming, ripping off roofs and shingles, destroying outbuildings and derailing empty train cars.

The twister, which carried winds of up to 135 mph, was part of a powerful storm system that rolled through parts of Colorado and Wyoming on Thursday, packing heavy rains, high winds and hail. The storms followed a round of nasty late spring weather that pummeled the region.

The tornado passed through a sparsely populated area near Wheatland, a small city about 70 miles north of Cheyenne. It left eight structures heavily damaged and caused lesser damage three structures, said Kelly Ruiz of the state's Office of Homeland Security.

Some power lines also were downed. Only one person suffered minor injuries.

Kim Eike said the tornado went right over her house, which was still standing, though battered.

"We lost a camper, it blew out the windows in our house, blew off the shingles clear down to the plywood, but we didn't lose the roof," Eike, whose property is about 8 miles south of Wheatland, said Friday.

Eike was watching the twister with co-workers at First State Bank in Wheatland when one pointed out it was near Eike's house. She said the pig barn and door from the main barn also were lost.

No one was home at the time, she said, noting that a couple in another house in the area rode out the storm in their basement.

Don Farrier, a Wheatland restaurateur, said his house about 6.5 miles from Wheatland was damaged and will need a new roof. He said he lost some trees, and a shed on his property was knocked down.

Farrier was at his restaurant when he saw the tornado and decided to drive toward his home.

"I stopped and watched it for a while," he said. "It sure wasn't moving very fast, but you could tell it was a big tornado for this part of the country."

National Weather Service meteorologist Richard Emanuel said the tornado was a quarter-mile wide and stayed on the ground for much of its 20-mile path from west of Wheatland to northeast of Chugwater. The area is about 60 miles north of Cheyenne.

Hail the size of golf balls also was reported in the Wheatland area, and 2-inch hail was reported in Laramie, the National Weather Service said.

The tornado knocked over five empty cars on a Burlington Northern Santa Fe train near parked Wheatland, railroad spokesman Gus Melonas said.

Preliminary reports show Colorado was hit by 10 tornadoes during the past two days. The storms came at the peak time for such severe weather in the state. Severe thunderstorms normally become less common later in the month and in early July until summer monsoons start developing.

At least seven homes were damaged in Elbert County on the plains southeast of Denver. County officials said two homes lost roofs and others had broken windows but the total damage was still being assessed.

To the south, four buildings and a house in El Paso County were heavily damaged, the National Weather Service said.

Laura Van Why said she and her husband Dennis, their 2-year-old son and two dogs hid under the stairs of their basement while the storm passed near Kiowa, Colo.

"It felt like forever," Van Why said. "It was like black out the windows."

Forecaster Jerry Claycomb with the National Weather Service in Cheyenne, said the same factors created the storms in both states.

A low-pressure system stalled over northern Colorado and against the Laramie Range mountains southeast of Casper. That pulled up low-level moisture from the Gulf of Mexico from the southeast.

High-level westerly winds combined with low-level southeasterly winds to create what Claycomb called "shear," which he said amounts to a turning in the atmosphere.

"It created these super cell thunderstorms over us, and those super cells created some tornadoes" he said.


Associated Press writer Rema Rahman contributed to this report from Denver.