We are now in meteorological spring, and severe weather has already reared its ugly head in the Deep South. Multiple tornadoes impacted locations in Tennessee, including near downtown Nashville, killing over a dozen people as of this post.
The threat of severe weather shifts to the Big Bend and South Georgia Wednesday into Thursday. The Storm Prediction Center has placed parts of the area under a slight (level 2 out of 5) risk of severe weather for most of the area Wednesday with the same level of threat extending eastward starting Thursday morning.
A somewhat complicated setup is expected to bring ample moisture along with lift aloft and at the surface, as well as enough wind shear to bring a threat for strong to severe thunderstorms.
For Wednesday, a front that is expected to move into the area will likely then move northward as a warm front. The location of the front will be key as to where the storms and heavy rain (more on the heavy rain later) would develop. The severe modes of concern will be damaging winds, isolated tornadoes, and a small risk of hail. Besides the surface front, some mid-level “energy” might also help to ignite rain and storms.
The threat will remain through Wednesday night into Thursday as a surface low develops over Texas Wednesday and moves eastward. Again, the placement of the warm front will be key on where the severe weather threat lies, but the front will likely lift more northward as the low moves through the Gulf coast states (see WPC graphic below). This will expand the severe weather threat northward and eastward Thursday morning into the afternoon.
The American GFS model (as of Tuesday afternoon) was a tad more aggressive with some of the parameters Thursday morning than the European run. But decent shear, moisture, and lift – especially with the incoming upper-level trough – will help set the stage for a low-end risk of isolated tornadoes and damaging winds Thursday.
With the front lingering and anomalously-high moisture available, there is the potential for heavy rain for the two-day period. Flash Flood watches are in effect for parts of South Georgia. Rainfall totals through Thursday could range between 1-2 inches along the coast to 3 to 4 inches in the South Georgia border counties.
Those in the Big Bend and South Georgia should be weather aware Wednesday, Wednesday night, and Thursday. Have a way to receive weather alerts on your phone and have a weather radio with an alert feature. Be sure they are functional before bedtime Wednesday night.