A woman walks her dog as a blizzard dropped snow over Boulder, Colo., Wednesday Dec. 19, 2012. A storm that has dumped more than a foot of snow in the Rocky Mountains is heading east and is forecast to bring the first major winter storm of the season to the central plains and Midwest.
Southern California is shivering under record cold with sub-freezing temperatures in the mountains and deserts.
Frost advisories are in effect for the mountains, valleys and some coastal areas until 9 a.m. Thursday.
The National Weather Service says the temperature dipped to 14 degrees in the high desert town of Lancaster Thursday morning, breaking a 2006 record low for the date. Neighboring Palmdale had 21.
Many other areas reported lows in the 30s and 40s. Los Angeles and San Diego hit 43.
Forecasters say a slight warming trend is expected later in the day through Friday, with Los Angeles and many other areas seeing highs in the 60s. The region will have a chance of some rain over the weekend.
The central U.S. saw its first major snowstorm of the season early Thursday, leaving at least three people dead, creating treacherous driving conditions and threatening to disrupt some of the nation's busiest airports ahead of the holiday weekend.
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Forecasters warned that heavy snow coupled with strong winds could create blizzard conditions from Kansas to Wisconsin – and guaranteed a white Christmas in some places – after the storm blanketed the Rocky Mountains earlier in the week.
The storm dropped nearly a foot of snow in Des Moines, but the storm wasn't as dangerous as earlier feared because everyone had good warning of the approaching havoc, said Kevin Skow, a National Weather Service meteorologist in the city. But wind might become a concern, he warned.
"It's starting to taper off," Skow said of the snow early Thursday. "It's soon going to become less of a snow event and more of a wind event."
The airport at Creston, Iowa, recorded the highest winds, with a gust of 53 mph. Skow said wind gusts would grow stronger later Thursday, creating whiteout conditions, before dying down by the evening.
On the southern edge of the storm system, high winds damaged homes and downed trees in central Arkansas, the weather service said. A powerful storm peeled the roofs off buildings and toppled trucks in Mobile, Ala., but injured no one. Tornado warnings remained in effect in parts of Mississippi, Louisiana and Alabama early Thursday.
Forecasters said the heaviest snow could be expected across a swath extending from northwestern Missouri into Milwaukee, Chicago and Michigan, with predictions of as much as a foot of snow in some areas. Before the storm, several cities in the Midwest had broken records for the number of consecutive days without measurable snow.
The weather service warned of poor visibility due to driving snow in much of the region and warned drivers to stay off roads in some areas. Transportation officials shut down parts of Interstate 29 in Missouri early Thursday, and Interstate 80 in Nebraska remained closed due to blowing snow.
In southeastern Wisconsin, where a blizzard warning was in effect and winds of up to 45 mph were expected to create whiteout conditions, sheriff's officials said slick conditions led to at least two fatalities late Wednesday when a driver lost control of his car in Rock County, about 90 miles northwest of Chicago. In southeastern Utah, a woman who tried to walk for help after her car became stuck in snow died Tuesday night. Search and rescue crews on snowmobiles found her buried in the snow just a few miles from her car.
Forecasters said snow would hit Chicago by mid-afternoon. Officials at the city's two international airports reported some delays and cancellations, but said most incoming and outgoing flights were on time. United Airlines said it would waive change fees for travelers who have to change their plans for travel through O'Hare International Airport.
Hundreds of schools across the affected region canceled classes Thursday because of heavy overnight snow. Kansas City Power & Light reported about 16,000 scattered power outages in northwest Missouri and northeast Kansas.