NORMAN, Okla. (AP) -- Heavy snow was expected to start falling overnight in the Rocky Mountains and western Plains as a strong storm system that forecasters say could eventually spawn tornadoes in the Midwest plowed eastward.
A winter storm warning or blizzard warning was in effect for parts of Utah, New Mexico, Wyoming, Colorado, Nebraska and Kansas from early Wednesday through the afternoon and evening in some places.
Northeastern Colorado and western Kansas and Nebraska, where the blizzard warning was in effect, could see up to 8 inches of snow and wind gusts up to 55 mph overnight — a combination that can cause white-out conditions.
The National Weather Service warned that traveling would be extremely dangerous and urged people to stay home.
A day earlier, up to 18 inches of wet, heavy snow fell in Nevada, shuttering schools in Reno and knocking out power to thousands.
At Pi Kappa Cino Coffee in Sterling, Colorado, workers on Tuesday were checking their heaters and stocking up on coffee to handle the first significant snowfall of the season.
"We always try to keep prepared for the winter, keeping extra water on hand and checking the heaters," owner Patricia Prescott said. "Business normally picks up because everyone wants our warm drinks."
Forecasters said earlier in the week that the system could also produce tornadoes as it moved further east.
"November has a history of producing some significant weather events. We will have to keep an eye on things," said Greg Carbin, warning coordination meteorologist at the Storm Prediction Center in Norman, Oklahoma.
An area from Nebraska to Illinois might face high winds, large hail and tornadoes Wednesday, forecasters said. A smaller threat existed across the Ozarks in Arkansas and Missouri, in the middle of the Mississippi River Valley, and as far south as central Texas.
The Storm Prediction Center's midday forecast Tuesday cautioned 54 million people to be alert for severe weather Wednesday.