A brutal winter storm closed interstate highways from Arizona to Wyoming Wednesday, trapped drivers in cars, knocked out power to hundreds of thousands of people and prompted the first blizzard warning in Southern California in decades — and the worst won’t be over for several days.

Few places were untouched by the wild weather, including some at the opposite extreme: long-standing record highs were broken in cities in the Midwest, mid-Atlantic and Southeast.

The wintry mix hit hard in the northern U.S., closing schools, offices, even shutting down the Minnesota Legislature. Travel was difficult. Weather contributed to more than 1,600 U.S. flight cancellations, according to the tracking service FlightAware. More than 400 of those were due to arrive or depart from the Minneapolis-St. Paul International Airport. Another 5,000-plus flights were delayed across the country.

At Denver International Airport, Taylor Dotson, her husband, Reggie, and their 4-year-old daughter, Raegan, faced a two-hour flight delay to Nashville on their way home to Belvidere, Tennessee.

Reggie Dotson was in Denver to interview for a job as an airline pilot.

“I think that’s kind of funny that we’ve experienced these types of delays when that’s what he’s looking into getting into now as a career,” Taylor Dotson said.

In Wyoming, rescuers tried to reach people stranded in vehicles but high winds and drifting snow created a “near-impossible situation” for them, said Sgt. Jeremy Beck of the Wyoming Highway Patrol.

“They know their locations, it’s just hard for them to get them,” he said.

Wyoming’s Transportation Department posted on social media that roads across much of the southern part of the state were impassable.