CHICAGO (AP) — A wall of storms packing ice, sleet and rain could upend holiday travel plans for Americans as millions take to the roads, skies and rails for Thanksgiving.

So far, the deadly storms barreling into the mid-Atlantic and Northeast have not resulted in many flight delays or cancellations, but forecasters are expecting the weather to worsen as the day wears on Wednesday.

National Weather Service spokesman Chris Vaccaro in Silver Spring, Md., says "the timing of the storm couldn't be worse." He says forecasters are "seeing numerous threats as the storm is beginning to develop and intensify."

According to AAA, more than 43 million people are expected to travel over the long holiday weekend. The overwhelming majority — about 39 million people — will be on the roads.