Most of the U.S. was forecast to experience a messy mix of rain, snow, ice on Thanksgiving morning, forecasters said.
"We have a little bit of everything with this system," said Domenica Davis, a meteorologist for The Weather Channel, who predicted that wet, wintry conditions would cover two-thirds of the United States.
Ice could make travel especially treacherous across the central part of the country from Kansas City, Missouri, south to Texas, Davis said.
Major flooding was predicted for large sections of Texas, Oklahoma and Arkansas through Friday.
Authorities in Wichita, Kansas, were already hard at work Wednesday hoping to keep the streets to Grandma's house clear on the holiday. Sixty trucks were out spreading sand and salt, and work crews were clearing debris from storm drains at 200 hot spots, NBC station KSNW reported.
"We could see our crews out in 12-hour shifts around the clock 24 hours starting Thanksgiving at midnight all the way through Monday morning," said Alan King, the director of public works.
Similar conditions were expected north and west.
Winter storm warnings were in effect Wednesday night for one or more counties in the Texas Panhandle, Nebraska, Oklahoma, Iowa, Nevada, Colorado, Idaho, Wyoming and Montana. The southern Wyoming town of Rock Springs was under a blizzard warning.
Wyoming — especially near Interstate 80 across the state — is "going to get hit very hard," said Danielle Banks, a meteorologist for The Weather Channel, while parts of northern New Mexico could get as much as 18 inches of snow.
The Colorado Transportation Department, meanwhile, had 202 pieces of snow removal equipment and 130 workers working 12-hour snow shifts just in metropolitan Denver on Wednesday, NBC station KUSA reported.
"Keep those winter weather survival kits in your car," Banks said.