The National Weather Service has increased the likelihood of severe weather, including tornadoes, in this weekend's forecast.
The latest data released Friday afternoon shows that a squall line is expected to enter the state late Saturday evening, and move through the metro Birmingham area starting around midnight, extending through the overnight hours of early Sunday. Ahead of this line, there's now an increased possibility of supercell thunderstorm formation, which may lead to isolated tornadoes.
This is not anticipated to be the type of situation often seen in the spring, with larger outbreaks of long-track tornadoes. Still, there's an increased danger because such storms may form during hours when most people are sleeping, so residents are encouraged to have a NOAA weather radio with an "wake-up" alarm function that goes off when warnings are issued.
There's still an elevated threat of damaging straight-line winds along the main squall line. The system is expected to move eastward and out of metro Birmingham before dawn on Sunday.
We'll have updates on this developing situation as they become available.