It's something very weird and nuanced going on right now,’ says one expert about the potential reasons for the snow blanketing much of the southern U.S.

A major winter storm slammed the southern US Tuesday, blanketing parts of the Gulf Coast with record-breaking snowfall in a region largely unaccustomed to extreme winter weather.

An historic January storm dumped more deep snow along the U.S. Gulf Coast on Wednesday after bringing Houston and New Orleans to a near standstill over the past two days and burying parts of Florida's Panhandle with accumulations more typical of Chicago.