(Reuters) - Freezing rain fell across much of the Great Plains and Midwest on Saturday as a major ice storm already blamed for the death of a motorist in Missouri and dozens of canceled flights threatened to wreak further havoc.
Ice, freezing rain and winter weather warnings and advisories were in effect for a vast swath of the country stretching from northern Texas east across parts of the Midwest and into the Washington D.C. area, according to the National Weather Service.
"Ice continues to accumulate in the Central/ Southern Plains states and will shift north into the Upper Mississippi Valley Sunday as a new weather system approaches from the West Coast," the Weather Service said on its website.
"This storm will change ice to snow from southeast Colorado to northeast Nebraska; and will bring a slight risk of severe thunderstorms and heavy rains to Texas on Sunday," the Weather Service said.
The Missouri State Highway Patrol urged motorists to avoid travel after 31-year-old Tiffany Jackson was killed while driving on any icy overpass in Crystal City. Jackson's vehicle slid off the road and struck trees, according to the highway patrol.
Forecasters said ice accumulation from the storm could be more than half an inch (1 cm). Snow, sleet and heavy fog were also in the forecast in parts of region.
Missouri and Oklahoma had declared states of emergency ahead of the storm as transportation officials in those states told motorists to avoid travel.
The Lambert-St. Louis International Airport told passengers to check with airlines as the weather "could potentially impact flights." Will Rogers Airport in Oklahoma City warned of "multiple delays and cancellations."
Airline tracking website Flightaware.com showed 435 flights had been canceled and nearly 5,000 delayed as of the afternoon.
Local news in Kansas City showed footage of shoppers rushing through stores to stock up on essentials.
"Getting stocked up for the upcoming ice storm and shelves are already empty," Tweeted Valerie Mia Juarez, a journalist in Nebraska, with a photo showing one loaf of bread on a bare shelf at a local Walmart.
The National Football League postponed the start time of a divisional playoff game between the Kansas City Chiefs and the Pittsburgh Steelers in Kansas City from around noon local time on Sunday to 7:20 pm.
As of Saturday morning, about 2,500 households and businesses were without power in Texas, Missouri and Oklahoma, utility companies reported.
Reporting by Brendan O'Brien in Milwaukee and Dan Whitcomb in Los Angeles; Editing by Angus MacSwan and David Gregorio