On Thursday, a negatively tilted upper-level trough will sweep northeastward into the Great Lakes, accompanied by a corresponding mid-level speed maximum of 70 to 80 knots. A cold front will move forward at the surface eastward into the mid-Mississippi Valley and Ark-La-Tex. By midday, surface dewpoints in the 60s F will be a contributing factor to weak instability in the majority of regions ahead of the front. As surface temperatures rise in the late morning, convection is anticipated to begin both ahead and along the front. In the afternoon, thunderstorms should progressively spread out over the lower to mid-Mississippi Valley and the lower Ohio Valley, heading eastward.

The primary threat appears to be damaging winds. While the SPC is not showing a tornado threat as of yet, I see a low-end threat. This is because I'm seeing a 3Cape of 67. Anything 50 and above shows a chance of a tornado forming. This, along with dewpoints possibly being in the mid-60s, is why I think there will be a low end tornado threat.  The SPC has issued a level 1 Marginal Risk for western Kentucky.

 

 

 

 

Daytime heating may result in destabilization from southwest OH across parts of KY, TN, and into the lower MS Valley, with new cells developing along the front. While deep layer shear and mean wind speeds in general will remain conducive for wind gusts, instability will be weak over northern areas.

The Storm Prediction Center has expanded the level 1 Marginal Risk Area eastward to include Cincinnati/NKY, Louisville and Bowling Green. The tornado threat is low but is not zero.