As the rain advances northeastward this morning, there is still a small threat that precipitation will begin as sleet before changing over to rain. The morning sounding at the Shelby County Airport showed a substantial warming in the layer from about 4,000 feet to 10,000 feet overnight. This warming of about 4 to 7 degrees plus the overall thickness of the warm layer will help to diminish the threat of frozen precipitation.
The dry layer at and just above the surface is still enough to create some evaporative cooling and potentially result in the precipitation beginning as sleet. However, I think that warm layer I described above will help to offset much if not all of that cooling.
It’s still wise to be cautious if you are traveling this morning especially north of a line from about Opelika to Jemison to Vernon. And that line will gradually advance northeastward, too, as the overrunning precipitation advances northeastward.
-Brian-
