The storm expected to bring more severe weather to the Mid-South late Tuesday shares many characteristics with the storm from the week before, although it is the differences between the storms that could potentially be more worrisome.
As always with severe weather events, I defer all discussion of the upcoming storm to the Storm Prediction Center. Their recent day 2 convective outlook discussion and the forecast discussion from the local NWS office in Louisville will be good references to check over the next 36 hours.
The primary difference between last Tuesday’s storm and this Tuesday’s storm has to do with the unseasonably warm airmass that has overspread the Mid-South. With temperatures near 70 and dewpoints in the low 60s expected for Tuesday afternoon, there will be plenty of moisture for these storms to work with. While the airmass behind the cold front is not nearly as cold as it was last week, there is still a very strong (>100 kt) jet core expected to be located directly over the Mid-South and plenty of wind shear. Tornadic supercells will develop in the warm sector Tuesday afternoon and will spread from AR and MS into the Mid-South through the afternoon. As the cold front approaches the region Tuesday evening/night, I would expect a powerful squall line to develop with possible bow echoes with tornadic potential, although straight-line wind damage will be more common.
I will update this blog frequently to reflect changes in SPC and LMK guidance over the next 24-36 hours.