Until then, expect lows in the mid 20s Thursday morning. It'll be clear and quiet enough for a hard freeze, so you'll need several extra minutes to defrost the cars in the morning. During the afternoon, it won't be quite as cold with highs near 50.
The pattern shifts a bit over the weekend. A strong low pressure system developing along the Gulf Coast slowly drags eastward. It sends a few showers northward into North Alabama this weekend, but the heaviest rain plagues south Alabama, Georgia, and north Florida. If your holiday travel takes you southeast, you'll be battling rain on the interstates.
Once the rain ends, the temperatures just keep climbing. Highs Christmas Eve and Christmas Day hit the mid 60s under mostly sunny skies.