Published: Feb 21, 2013 6:12 AM EST
Updated: Feb 21, 2013 12:40 PM EST

ST. LOUIS (AP) - Much of the nation's heartland awoke Thursday to heavy snow, treacherous roads and a day off from work or school as a large, potentially dangerous winter storm pushed eastward out of the Rockies.
    
Winter storm warnings were issued from eastern Colorado through Illinois. More than a foot of snow was expected in some places; a slippery mix of snow, sleet and freezing rain in others. Schools cancelled classes, sporting events had to reschedule and even lawmakers were staying home. Hundreds of flights were cancelled.
    
Kelly Sugden, a National Weather Service meteorologist in Dodge City, Kan., said early Thursday that the storm, which had been moving slower than expected, clipped Colorado and western Kansas on Wednesday and was "starting to get back together."
    
"It's very active," Sugden said, noting the snowfall in some places was mixed with lightning and sleet showers. On Thursday morning, Kansas City, Mo., experienced rare "thundersnow" - heavy snowfall accompanied by occasional thunder.
    
Sugden said forecasters weren't expecting blizzard conditions to develop in Kansas, but the Interstate 70 corridor could get as much as 13 inches of snow, and large drifts would make for treacherous driving conditions.
    
Near the Nebraska-Kansas border, as much as 8 inches fell overnight, while western Nebraska saw about half of that amount, National Weather Service forecaster Shawn Jacobs said Thursday.
    
Some parts of Oklahoma also had up to 8 inches of snow by Thursday morning, and the weather caused a fatal wreck Wednesday. The Oklahoma Highway Patrol said 18-year-old Cody Alexander of Alex, Okla., died when his pickup truck skidded on a slushy roadway into oncoming traffic on a state highway and struck a truck. The other driver wasn't seriously injured.
    
In northern Arkansas, a school bus crashed Wednesday on a steep, snowy country road, leaving three students and the driver with minor injuries. Pope County Sheriff Aaron Duval said the bus slid off a road on Crow Mountain, nearly flipping before it was stopped by trees.
    
The weather service warned that freezing rain could lead to a half-inch or more of ice accumulating Thursday in central and northern Arkansas.
    
In Kansas, transportation officials - and even the governor - urged people to simply stay home after a blanket of snow covered most of the state by early Thursday.
    
The Kansas Turnpike Authority encouraged drivers to stay off the turnpike entirely; it runs from Oklahoma to Kansas City. There was virtually zero visibility on the turnpike early Thursday. And I-70 and other major highways in Kansas were snowpacked and icy, according to the Kansas Department of Transportation.
    
Kansas Gov. Sam Brownback closed executive offices, except for essential personnel. He urged residents to have an extra cup of coffee, get out a board game and play with their children.
    
"Common sense is a good thing, and we'll make it through it," Brownback said.
    
State legislatures in Arkansas, Kansas and Missouri called off all meetings Thursday, and lawmakers in Nebraska and Iowa cancelled afternoon activities.
    
Thousands of schools, including some colleges, from Colorado through Illinois shut down. A Big 10 men's basketball game between Iowa and Nebraska originally scheduled for Thursday in Lincoln, Neb., was moved to Saturday.
    
The storm didn't stop everyone. Jesse Landin, feedlot manager at McClymont Feedyard in south-central Nebraska, was out early Thursday clearing a path with his tractor so trucks could put down feed for 11,000 head of cattle, which remained outside.
    
"They can handle it," Landin said of the cattle. "They got good winter hair coats."
    
In Jefferson City, Mo., off-duty police sergeant Randy Werner had been perched atop a hotel for more than 24 hours as a publicity stunt for a charitable fundraiser.
    
As large blowing snowflakes pelted him in the face Thursday morning, Werner defiantly declared: "The weather's not bothering me, I can assure you." He then acknowledged that was a lie.
    
"It's blustery," he said. Werner planned to cut his camp out short, having raised less than a third of his goal.
    
Snow was coming down fast than the fleet of plows in Kansas City, Mo., could move it Thursday, and morning rush-hour traffic slowed to a crawl. Visibility dropped drastically by mid-morning downtown, removing downtown skyscrapers from view.
    
The Missouri Department of Transportation said Interstate 44 near Springfield was completely covered with ice Thursday morning. Traffic was moving very slow and the DOT urged drivers to use extreme caution or stay home.
    
St. Louis-area road crews were out in full force early Thursday, even though it was dry. The region was expecting a volatile mix of snow, sleet, ice and freezing rain by midday and crews were hoping to lay down enough salt to keep at least the major roadways moving.
    
Officials feared the winter storm would be the worst in the Midwest since the two-day Groundhog Day blizzard in 2011. It was blamed for about two dozen deaths and left hundreds of thousands without power, some for several days. At its peak, the storm created white-out conditions so intense that Interstate 70 was shut down across the entire state of Missouri.
    
National Weather Service meteorologist Jayson Gosselin said precipitation is generally expected to drop off as the storm pushes east. Chicago and parts of Indiana, he said, could get about 2 inches of snow and some sleet.
    
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Associated Press writers Chris Clark in Kansas City, Mo.; Josh Funk and Nelson Lampe in Omaha, Neb.; Roxana Hegeman in Wichita, Kan.; David A. Lieb in Jefferson City, Mo.; Colleen Slevin in Denver; and M. David Nichols in Chicago contributed to this report.

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