Thousands of residents in two communities near Denver were ordered to evacuate Thursday because of a wind-fueled wildfire that engulfed parts of the area in smoky, orangish skies.

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The city of Louisville, which has a population of about 21,000, was ordered to evacuate after residents in Superior, which has 13,000 residents, were told to leave. The neighboring towns are roughly 20 miles (32 kilometers) northwest of Denver.

A nearby portion of U.S. Highway 36 also was shut down because of fire.

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The blaze near the towns was one of several that started in the area Thursday, at least some sparked by downed powerlines, as winds gusted up to 105 mph (169 kph) and sent flames racing through barren trees, according to the National Weather Service.

Colorado’s Front Range, where most of the state’s population lives, had an extremely dry and mild fall, and winter so far has continued to be mostly dry. Snow was expected Friday in the region though.

Video captured by a bystander outside a Superior Costco store showed winds whipping through trees in the parking lot surrounded by gray skies, a hazy sun and small fires scattered across the ground.

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Leah Angstman and her husband saw similar skies while returning to their Louisville home from Denver International Airport after being away for the holidays. As they were sitting on the bus going toward Boulder, Angstman recalled instantly leaving clear blue skies and entering clouds of brown and yellow smoke.

“The wind rocked the bus so hard that I thought the bus would tip,” she wrote in a message to The Associated Press.

The visibility was so poor that the bus had to pull over and they waited a half-hour until a regional transit authority van escorted them to a turnaround on the highway. There she saw four separate fires burning in bushes across the freeway, she said.

“The sky was dark, dark brown, and the dirt was blowing in swirls across the sidewalk like snakes,” she said.

The evacuations come as climate change is making weather more extreme and wildfires more frequent and destructive, scientists say. A historic drought and heat waves have made wildfires harder to fight in the U.S. West.