DENVER — A snowstorm sweeping through Colorado and Wyoming on Sunday was expected to bring as much as four feet of snow to some parts of the region, and has left more than 30,000 people without power in Colorado.
The storm brought heavy, wet snow and downed trees and power lines. More than 25,000 customers near Greeley, Colo., about 50 miles north of Denver, were without power on Sunday, according to Xcel Energy. About 5,000 people around Fort Collins and about 1,000 people in the Denver suburbs were also without power.
A blizzard warning was in effect on Sunday for Colorado’s Front Range, an area that includes the Interstate 25 corridor from south of Denver up through Cheyenne, Wyo.
The National Weather Service warned that an additional two to six inches of snow and wind gusts as high as 45 miles per hour could create “nearly impossible travel conditions.”
As of Sunday afternoon, more than 19 inches had fallen at Denver International Airport, making it the city’s largest snowstorm since 2016, said Kylie Bearse, a meteorologist at 9News in Denver.
The storm was the city’s 11th-largest snowstorm on record and was on track to reach the top 10 “pretty easily,” she said. Forecasters expected the snow to continue through early Monday morning.
Estes Park, a town about 30 miles northwest of Boulder, could get two to four feet of snow, Ms. Bearse said. She added that Cheyenne was expected to get as much as 32 inches of snow and had already gotten 25.8 inches this weekend, breaking a record of 25.6 inches set in 1979.
Colorado had been bracing for this snowstorm: Gov. Jared Polis activated the Colorado National Guard, grocery store shelves were left bare by Friday as shoppers prepared for the storm and Denver International Airport canceled nearly 750 flights on Saturday and more than 1,200 flights on Sunday.
The airport said on Twitter on Sunday that it had closed all of its runways “due to blowing snow and poor visibility.”
Eldora Mountain, a ski area on the Front Range that is about 20 miles west of Boulder, had gotten 11 inches of snow since Saturday afternoon, and was expecting up to 23 inches in additional snow on Sunday, according to Open Snow, which provides forecasts for ski resorts.
Though Colorado is known for its late-season snowfall — March is Denver’s snowiest month on average — “it’s definitely a rare event,” Ms. Bearse said, “to get this much snow.”
Much of the snow was falling on Colorado’s Front Range and Foothills, leaving its more mountainous High Country without such intense snowfall because of an “upslope event” that brought wind from the east, she said.
Parts of major roadways, like Interstate 80 in Wyoming and Interstate 70 between Denver and Silverthorne, Colo., near many of the state’s ski areas, were closed overnight on Saturday, and a section of Interstate 70 was closed again on Sunday afternoon.
The Colorado State Patrol said on Twitter that snowplows were stuck or overturned on the roads.
Denver’s transportation authority said on Twitter that, because of blizzard conditions, all of its bus and rail operations were experiencing significant delays. “All travel is discouraged at this time unless it is critical,” it said.
Amanda Nebelsick, a Fort Collins resident, lost power for about seven hours on Sunday morning.
Her neighbors hosted a pancake breakfast for those who were unable to cook on Sunday, she said, and her normal view of the mountains was blocked by heavy snowfall.
“Now that the power’s back on, we’ll just hunker down and enjoy the afternoon,” she said.
Snow had been forecast to start falling early Saturday in Denver, but higher temperatures caused the snow to fall instead as a drizzle, Ms. Bearse said. The storm also moved into the area more slowly than anticipated, leaving many Denverites — including Ms. Bearse — underwhelmed by the snowfall totals on Saturday.
“I was frustrated seeing that storm come in so slowly,” she said, adding, “I barely slept last night.”
More snowstorms are likely in the state through March and April, with snow expected this week and next week in Denver.
The storm is set to move on from Colorado and Wyoming on Monday morning, bringing a mix of rain and snow to the Midwest on Monday, Ms. Bearse said. It is expected to bring rain to the East Coast and potentially snow to parts of New England on Tuesday.