The death toll has risen to six from winter storms in the U.S. midsection that are pushing toward the Northeast.
Two passengers in a car on a sleet-slickened Arkansas highway died Wednesday when the vehicle crossed the centre line and struck an SUV.
In Oklahoma, the Highway Patrol said a 76-year-old woman died Tuesday when a truck crossed into oncoming traffic and hit the car she was in. The Highway Patrol earlier reported that a 28-year-old woman was killed in another crash.
The storm's winds were also blamed Tuesday for toppling a tree onto a truck in Texas, killing the driver, and a tree onto a house in Louisiana, killing a man.
More than 325 flights around the U.S. were cancelled as of Wednesday morning, according to the flight tracker FlightAware.com. Most were at airports in the path of the storm.