The Storm Forecast Center says there is a high probability of tornadoes – a level 5 out of 5 – for parts of the south. Those are the worst and highest forecasts for severe storms. And while the SPC is very rare to issue this kind of forecast, it is now the second time in a week for the South.
The SPC warns of “several long track tornadoes, devastating winds, and very large hail forecasts from the Lower Mississippi Valley, east across parts of the southeast and north into the Tennessee and Ohio Valleys.”
Some of the widespread winds will be “hurricane-force,” the SPC said, while some areas may see hail that is “baseball-sized.”
Long trajectory tornadoes are tornadoes that stay on the ground for an extended period of time. Most tornadoes are on the ground for just minutes, but some serious events can have tornadoes on the ground for hours. This type of tornado is known for causing widespread damage.
More than a million people are threatened by tornadoes, including in cities like Decatur and Madison in Alabama and Florence in Mississippi.
More than seven million people are in areas of moderate tornado threat – a level 4 out of 5 – including Memphis and Nashville in Tennessee, Birmingham and Huntsville in Alabama and Jackson, Mississippi.
“The ingredients will be combined on Thursday for another severe weather outbreak in the south,” said CNN meteorologist Chad Myers. “Highly humid air in the Gulf of Mexico combined with strong upward movement will cause multiple rounds of severe weather, including rotating storms that can trigger tornadoes.”
Ingredients were there last week and tornadoes developed, but not as strongly as predictors thought possible. None of the 49 tornadoes was stronger than an EF-2 on a 0 to 5 scale.
While the right atmospheric ingredients were in place, they didn’t mix exactly enough to produce the violent tornadoes predicted last Thursday.
“It’s like putting too many carrots in chicken soup, you end up with sweet carrot soup and not chicken soup,” Myers said.
The threat is greatest this afternoon and tonight
Violent storms will hit the Deep South on Thursday as the risk area for severe storms is likely to grow and expand. Strong storms will be possible from the Gulf Coast to northern Ohio.
On Thursday morning, some stronger storms could be possible in this risk area, but the most active weather starts in the afternoon when multiple supercell thunderstorms could form.
“Right now, the best potential for strong tornadoes appears to be extending from parts of central / northern MS to western / mid-TN and central / northern AL, especially Thursday afternoon and evening as storms generally move to the Northeast” , the SPC said Wednesday afternoon.
The forecast shows that atmospheric conditions will be ripe and “support supercells with low mesocyclones capable of producing strong tornadoes and large hail,” the SPC said.
And it’s not just tornadoes: More than six million people were kept under flash guard early Thursday in parts of Tennessee, Alabama, Georgia and North Carolina. Rainfall of up to four inches is expected in the region, and higher amounts are expected in some areas.
During the night hours of Thursday, the storms are expected to evolve into a line running to parts of Alabama and Georgia. Friday should dry most of the south, except for parts of Georgia and the Carolinas, where weaker showers and isolated thunderstorms can linger.
School systems change plans because of the weather
School districts across the region are changing plans, firing students early, going online learning and canceling classes ahead of Thursday’s severe weather.
In Alabama, Anniston City Schools told parents via social media that students would have an E-day on Thursday. Gadsden City Schools announced they would be closing due to the storm.
Huntsville City Schools are firing students prematurely. Tuscaloosa County Schools announced that they would have a system-wide day of distance learning. Birmingham City Schools are also planning a full day out of the way for Thursday.
Demopolis City and Limestone County school officials also announced plans to fire the classes early.
“If for some reason students don’t have power or internet, they can make up for the job,” school district officials posted on social media. “The domes on every campus will also open tomorrow if someone needs shelter.”
CNN’s Robert Shackelford and Dave Alsup contributed to this report.