A strengthening storm spells travel trouble for millions from the Four Corners to the Midwest.
The storm has already crippled highways across higher elevations of Arizona, where more than a half-foot of snow fell on Flagstaff, Arizona, and accidents forced the Department of Transportation to close roads to clear accidents.
BLIZZARD EXPECTED TO HIT AS WINTER STORMS BLANKET ROCKIES, PLAINS, UPPER MIDWEST
HIGH WINDS CAUSE DANGEROUS DUST STORMS IN CALIFORNIA, FLIGHT DELAYS IN LAS VEGAS
Winter Storm Watches and Warnings were issued from the New Mexico and Colorado through parts of Illinois.
Across the Plains, confidence is increasing that an area of heavy snow is likely from northern Kansas through Iowa and Wisconsin. This snow will begin Wednesday night and last into Friday.
Travel impacts are likely, along with school closures. Exact snowfall amounts remain uncertain, but 5-plus inches of snow appears likely.
Some areas of Colorado and New Mexico are in for up to a foot of snow, starting in the morning.
By the evening, snow starts across Kansas, Iowa, Minnesota and Wisconsin. The FOX Forecast Center calls for snow falling at one-inch per hour rates. Wind gusts over 40 mph will create blizzard-like conditions.
Omaha, Milwaukee and Chicago will start off with rain which prevents crews from pre-treating roads. That will mean slippery driving as the cold works its way in heading into Thursday.
The snow will taper off for Colorado but continue for the Northern and Central Plains through Thursday. Most cities will see 3 to 6 inches of snow wrapping up late evening and early Friday.
And while many in the central U.S. could see snow by Friday, the southern side of this low-pressure will bring severe weather to parts of the South and Southeast.
TORNADOES, LARGE HAIL, DAMAGING WINDS THREATEN SOUTH OHIO VALLEY
Thunderstorms, which can potentially turn severe, could trigger flooding rain, dangerous lightning, large hail and possibly tornadoes.