Thursday’s fire sent plumes of smoke and fire into the sky, reducing visibility. Several houses caught fire in the pictures. Firefighters fought to protect other residences.
The cities – Louisville and Superior – are about 4 miles apart, not too far from Boulder.
A spokesperson for UCHealth told CNN that at least six people are being treated for injuries related to the fire. Kelly Christensen said no further information is available for the patients, who are at UCHealth Broomfield Hospital.
Another hospital, Evista Adventist Hospital, was prompted to evacuate its patients and staff. According to its website, the facility has 114 beds.
The U.S. Census Bureau says there are about 21,000 residents in Louisville and 13,000 in Superior.
“We are in the middle of a truly historic storm at the front boundary, foothills and urban corridor,” the National Weather Service office in Boulder said.
Widespread wind gusts of 80-100 mph have been observed, the weather service said, and “a handful of sites in the Rocky Flats have seen gusts of 100-115 mph for several hours.”
County residents have been told to evacuate if they see flames from one of the many wildfires.
The reported hurricane-force wind gusts are being attributed to “extraordinary mountain wave amplification”, a large increase in wind speed as the wind blows down and down the mountains into low altitudes that are very specific atmospheric. Huh. There may be circumstances.
Strong wind warnings are in place for parts of Colorado and Wyoming through this evening. Winds with gusts of 25 to 40 mph are forecast with gusts of more than 80 mph.
“The strongest winds below 6000 feet are expected near the base of the foothills from Boulder north from Fort Collins to the Wyoming border,” the weather service said.
In addition to the fast-spreading fire, these strong winds will blow up trees and power lines, causing widespread power cuts and difficult travel.
The NWS office said a “rapid retreat of the strongest winds in the foothills” is expected by Thursday evening.
By morning, the area going “from fire to snow” will be “weather in the grip,” according to the weather service. An advance cold front will push into the region and bring snow showers to the foothills and front boundary by sunrise.
A winter storm warning is in effect for the area beginning at 5 a.m. Friday and 5-10 inches of snow has been called for Saturday. The combination of heavy snow and winds associated with the front and the terrain will at times create dangerous travel conditions.
“Prayers for the thousands of families recovering from the fires in Superior and Boulder counties,” he tweeted.
Later, he declared a state of emergency for the area.
CNN’s Haley Brink and Brandon Miller contributed to this report.