The TN Valley appears to be the center of likely severe-storm development, extending from south-central Kentucky. Strong deep-layer shear and hodographs would favor supercells in this corridor, which should have a better chance of weak to modest destabilization. A level 2-slight area appears to be warranted due to the consensus of model guidance regarding late afternoon to early evening storm development along/ahead of the front. The degree of early destabilization will determine how severe and widespread the threat may become. Friday night's subsiding large-scale rising motion from the southwest to the northeast casts doubt on how long the severe weather will last.

A level 1 marginal risk area surrounds the level 2 slight risk area. 

 

BGP Weather Update:

Precipitation will continue into the early afternoon. As warm, humid air is brought into Kentucky by the low-level jet's southwesterly winds, temperatures will primarily rise. Highs in the mid- to upper 60s are possible in parts of Kentucky west of I-65. Dew points will increase to the low 60s at the same time. This will serve as fuel for any potential storms. 

The upper jet's predominantly zonal flow and westerly to southwesterly winds are one factor limiting the development of supercells or tornadoes. For any storms to rotate and form supercells, there must be a greater change in wind direction with altitude. This could change along with the conditions. There must be a trigger for severe storms to form. This could be the little ripples in the upper-level jet. These are pointed out by the black arrows.

 

 

Up to 25% of supercell development is predicted by the most recent GEFS Ensemble model. Everyone can see that these conditions are almost exactly where the level 2 slight risk area is located on the maps. 
Throughout the evening, precipitation will increase its coverage. 

When new information becomes available, I will provide another update. 

 

 

Low-level Jet

Upper-level jet

 

Simulated GFS radar