Vehicle accidents resulting from icy, snow-covered roads were already being reported on Saturday evening.
Jefferson City Police Department Sgt. Gary Campbell said between 11 p.m. Friday and around 2 p.m. Saturday, the department responded to 46 accidents.
Missouri's governor Mike Parson said on Twitter that he had been briefed by public safety agencies and warned drivers to stay off the roads "as our dedicated road and emergency crews continue to fight this storm".
The University of Missouri men's basketball game at the University of SC was also canceled Saturday because of weather-related travel problems, the team tweeted. The team followed up later on saying the game was "tentatively rescheduled for Sunday".
The FlightAware.com flight tracking website reported 1,431 flight cancellations on Friday and 12,465 delays, with problems at snow-hit airports like Denver causing knock-on effects around the country.
A winter storm that buried the US Midwest in snow has resulted in at least five roadway deaths.
The Weather Channel's Jim Cantore, reporting Saturday morning from the interstate west of St. Louis, noted that many people remained stuck in conditions he called "horrible".
The storm will gear up across central Colorado, then move east across the Plains.
Sunday brings some clearing, with partly cloudy skies expected by the afternoon and highs in the low to mid 30s. Parts of Iowa, Kansas and Nebraska all received more than 10 inches of snow.
There is about a 10 percent chance that St. Louis will get 15 inches or more of snow, according to the National Weather Service high-end forecast.
In a lighter storm-related moment, the Chiefs released a video of quarterback Patrick Mahone strolling through the snow at Arrowhead Stadium. In St. Louis on Friday night, parts of I-44, I-55, I-64 and I-70 were partially closed because of current snowfall, and more is on the way. "This is where the highest accumulations of (3 inches or more) are expected".
The system was spreading into the Mid-Atlantic region Saturday afternoon.
A winter storm that dumped heavy snow on the U.S. Midwest, stranding some motorists in Missouri and canceling dozens of flights, marched east toward Washington on Saturday.
The National Weather Service (NWS) reported that Northern Missouri and central IL will be hit the hardest.
There is a small chance that the southern Appalachians get enough freezing rain and sleet to turn into an ice event Saturday into Sunday.
More heavy rain also will fall on the already-saturated South.