The National Weather Service calls for snow, ice or a "wintery mix" across much of the nation.
This post was updated at 4:30 p.m. ET.
It already has an ominous-sounding name: Winter Storm Titan. And it has much of the nation's mid-section in its sights.
The storm is the same system that that caused flash-flooding in California on Saturday and is now heading the Midwest and the Deep South on Sunday, where it will dump snow, ice or some combination of the two over a large swath of the country, according to The Weather Channel.
The National Weather Service said Titan will move over the Rockies, Plans and Mississippi Valley through Sunday. Parts of Kansas, Oklahoma, Missouri, Arkansas, Tennessee, Mississippi, Kentucky, Indiana, West Virginia, Virginia Pennsylvania, Maryland, Delaware and New Jersey are under a winter storm warning.
The NWS warns of "very hazardous travel [Sunday] evening through Monday," for many areas.
"Widespread power outages are likely in areas where freezing rain accumulates on tree limbs as the storm moves through the Midwest, the Weather Channel warned."
"Colorado's ski resorts could see up to six inches of fresh snow. A mixture of sleet and snow in Kansas, Missouri and Illinois will eventually change over to all snow — with up to 8 inches forecast for Kansas City and the St. Louis area — while northern Arkansas will see freezing rain."
"But eyes are already turning to the Appalachians and the East Coast, where the wintry mix will turn to snow during Sunday afternoon and into Monday."
The Washington Post's Capital Weather Gang blog forecasts between 5 and 9 inches of snowfall for the D.C. area. The NWS subsequently issued a warning for the region, calling for 6 to 10 inches of accumulation.
"The storm is forecast to bring ice to Dallas and snow from Kansas City, Missouri, to Indianapolis before arriving on the East Coast later today. Nationwide, 3,103 flights are already canceled through tomorrow as of 3 p.m. New York time today, said FlightAware, a Houston-based airline tracking service."
"The majority of trips scrubbed today were out of Dallas/Fort Worth International Airport and Chicago's O'Hare International Airport, the company said."
"'Monday morning's commute will be particularly difficult,' the weather service said in a winter storm watch issued last night covering an area from southern New Jersey to eastern Pennsylvania."