Undated (AP) _ A storm that buried parts of Colorado and Wyoming under 4 feet of snow turned into freezing rain as it moved eastward, snapping power lines and turning roadways into ice rinks. Half the homes in Des Moines, Iowa, were without power today.

The snow cleanup was expected to get easier today, with temperatures expected to soar into the 50s.

''When you step off the curb, you're probably going to step into a slush pile,'' Craig Sanders, forecaster for the National Weather Service said Wednesday night in Cheyenne, Wyo.

About 130 miles of interstate highway were still closed in Wyoming early today as crews tried to clear snow drifts and abandoned cars. The storm dumped up to 50 inches of snow in parts of northern Colorado and shut down travel from the Denver area to southeastern Wyoming.

South of the snow belt, the weather system produced as much as 7 inches of rain overnight in parts of Arkansas, and a school bus was swept off a flooded road and into a rain-swollen ditch today near Cabot, northeast of Little Rock, Lonoke County officials said. Students had to be rescued by pontoon boat but none was injured, said dispatcher Barbara Eddy.

The fierce storm, driven by winds up to 50 mph, was blamed for at least one traffic death in Colorado, and some highways were closed and littered with stuck and stalled vehicles Wednesday.

The freezing rain moved into Iowa, Nebraska, South Dakota, Wisconsin and Minnesota, coating power lines, roads and tree limbs and knocking out electricity.

''It's just like an ice skating rink on the interstate,'' said Bob Gantz, a mechanic for Dave's Auto Repair in Ankeny, Iowa. ''The patrolmen couldn't even stand up on the pavement to direct traffic.''

Hundreds of schools closed or opened late today in the Minneapolis-St. Paul area. Snow and sleet became mixed with rain early today, with an inch or two of snow reported in parts of central Minnesota, the weather service said.

''Definitely (I) wouldn't want to travel today if I didn't have to,'' said forecaster Bill Harrison of the National Weather Service in Minneapolis.

Half of the village of Hemingford in the Nebraska Panhandle lost electricity Wednesday, as branches fell on power lines. ''It sounds like we have a lot of lumberjacks outside,'' said Peggy Reynold, administrator in the village of 1,023.

At least 90,000 Iowa Power customers in central Iowa were without electricity today, and company spokesman John McCarroll said it may be the largest winter outage in the company's history. Schools were closed for the first time this winter in Des Moines.

Police said nearly every street in Des Moines was closed or partly closed at some point by downed lines or fallen limbs. Thick fog covered the city early today, cutting visibility during morning rush-hour traffic.

Commuters in Colorado today faced slush-covered highways, still strewn with abandoned vehicles. The public transit system in Denver was back on schedule today, after cancellation of up to 30 bus routes Wednesday. But at least two school districts decided to keep all schools closed for another day.

Snow continued to fall overnight in southern Wyoming, northern Colorado and southwest Nebraska. Freezing rain extended from north-central Nebraska across parts of South Dakota, the southern half of Minnesota and parts of Iowa.

Rain and a few thunderstorms reached from western Wisconsin across western Illinois, and parts of Iowa, Missouri, Nebraska, Kansas, Arkansas, Mississippi, Alabama, Tennessee and Kentucky.

The heavy ice brought opportunities as well. In Webster City, Iowa, a 74- year-old man startled patrons of a truck stop by whizzing around the parking lot on a 50-year-old pair of hockey skates.

''It's the best skating I've had all winter,'' said Elmer Clare.

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