Authorities issued alerts and shut down schools and government offices across Denver and other Rocky Mountain and Plains communities.
The U.S. National Weather Service issued blizzard warnings for northeastern Colorado, southeastern Wyoming, western Nebraska and parts of the Dakotas.
Forecasters said they expect winds of up to 70 miles per hour (110 km per hour) to sweep across a wide area of states to the south, including New Mexico and parts of Texas, Oklahoma and Kansas.
Around Denver, the most populated area covered by the blizzard warnings, rain was expected to turn into snow on Wednesday morning and continue into the night as the storm moves eastward to the Upper Midwest, where snow will end on Thursday (March 14), according to forecasters.
The storm threat had already forced the cancellation of more than half the nearly 1,050 flights into or out of Denver International Airport by early Wednesday, according to the tracking site FlightAware.
Airlines canceling flights going to or from Denver included Southwest Airlines , United Airlines and Frontier Airlines, the airport said.
(Production: Omar Younis)