A storm that toppled power lines, closed major highways and buried parts of the southern Plains in heavy ice and snow began moving into the South on Friday.

Winter storm warnings were in effect from New Mexico to North Carolina, and Arkansas Gov. Mike Beebe declared a state of emergency. The storm threatened to dump up to a foot of snow across the region after leaving 13 inches in the northern Texas Panhandle, where nearly all of Interstate 40 from the Texas-Oklahoma line to New Mexico was closed.

“There’s probably 3 1/2 inches of packed ice on the road. And it’s no snow, it’s all ice,” said David Hill of Oklahoma City, who was hauling a load of food products. “I’ve probably got 2 inches that covers my whole tractor. It’s pure ice.”

Flights were canceled Friday morning at airports in Oklahoma City and Little Rock, Ark.

Arkansas State Police warned people who were driving to work on Friday to be prepared to be stranded. Spokesman Bill Sadler encouraged motorists to bring blankets, water and snacks with them and to line up a hotel room within walking distance or otherwise plan for an overnight stay.

The snow, sleet and freezing rain were expected to crawl east through Friday. In Arkansas, as much as a foot of snow could fall near the Missouri state line, northern parts of central Tennessee could see up to 8 inches and western North Carolina could get hit with a foot of snow, according to the National Weather Service.

More snow also was expected in Texas and Oklahoma, where dozens of shelters were opened for those who needed a warm place to stay, including First United Methodist Church in Hobart, about 120 miles southwest of Oklahoma City. Pastor Kyle Clark said downed trees and utility poles littered the slick roadways and most of the town of about 4,000 residents had no electricity.

More than two dozen flights were canceled Friday morning at Will Rogers World Airport in Oklahoma City following the cancellation of more than 100 flights Thursday because of concerns about ice buildup on planes, according to the airport’s Web site. In Arkansas, Little Rock National Airport reported that a number of flights were canceled.

Flights also were canceled Thursday in Tulsa and in Texas out of Lubbock, Amarillo and Wichita Falls.