Cobb County and much of north and central Georgia is under a tornado watch until 11 p.m. Thursday.
The National Weather Service also has issued a hazardous weather outlook for the rest of the evening as a system of thunderstorms and high winds is moving in from Alabama.
At least one major outdoor public activity in East Cobb has been called off. Cobb communications director Robert Quigley said that tonight's Menorah lighting at East Cobb Park . He said a possible rescheduling the event is uncertain for the time being.
Unseasonably warm temperatures greeted the first official day of winter in Georgia, with highs in the metro Atlanta area nearing 70.
The NWS forecast for the rest of Thursday calls for stronger rains, thunderstorms and damaging winds as the evening progresses.
Those conditions, according to the NWS, are strongest between 4 p.m. and 9 p.m. Thursday.
But rains will continue overnight, with low temperatures around 50.
More rain is expected early Friday with highs around 60 and lows in around 40.
Temperatures are forecast to get cooler through the Christmas holiday, with sunny skies on Saturday and another chance of rain on Sunday.