At 3:13 a.m. Saturday, the National Weather Service issued an updated freeze warning in effect until 8 a.m. for Marion, Lamar, Fayette, Winston, Walker, Blount, Etowah, Calhoun, Cherokee, Cleburne, Pickens, Tuscaloosa, Jefferson, Shelby, St. Clair, Talladega, Clay, Randolph, Sumter, Greene, Hale, Perry, Bibb, Chilton, Coosa, Tallapoosa, Chambers, Marengo, Dallas, Autauga, Lowndes, Elmore, Montgomery, Macon and Bullock counties.

The weather service says to predict, “Minus degrees as low as 30 degrees.”

“Frost and freezing conditions can kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing,” the weather service explains. “Take measures now to protect tender plants from cold. To prevent freezing and possible bursting of pipes, they should be wrapped, drained or allowed to drip slowly. Those with in-ground sprinkler systems should drain them and cover pipes above ground to protect them from freezing.”

Freeze watch or warning – this is what it means

Freeze warnings are issued from May to October (but may be extended if necessary), when low temperatures are expected to be 29-32 degrees. If there is a potential for temperatures to fall below these thresholds, a freeze watch may be issued a few days in advance.

According to the weather service, if a freeze warning or watch is issued for your area, there is little you can do to protect plants. If you can move your sensitive plants inside, do so as the freeze will likely kill them, depending on the severity of the conditions.

Advance Local Weather Alerts is a service provided by United Robots, which uses machine learning to compile the latest data from the National Weather Service.