I figured I would get this started.
There are a lot of pieces on the board for a fairly significant event here. BL moisture quality is one of them, most guidance agrees on getting mid-upper 60s dewpoints over a rather expansive piece of real estate from the Arklamiss and Mid South eastward into the TN Valley on Saturday afternoon. The timing of the trough is another, with it kicking negatively tilted and ejecting ENE right during peak heating on Saturday. The wind fields are obviously strong given time of year and intensity of the shortwave. Shear vectors are well aligned with the pre-frontal trough to encourage semi-discrete/discrete storm modes assuming initiation.
I would like to see a bit more confidence on some drying aloft ahead of the pre-frontal surface trough (perhaps with some cloud breaks to increase instability a bit more) and also some more confidence in at least southerly surface winds ahead of the same feature. I also have concerns about the degree of warming aloft, as 500 mb and 300 mb temps are not particularly cold.
The 12z CIPS run for the SE domain showed a rather impressive list of analogs including at least 7 that resulted in at least one F/EF3 tornado in the region, which is quite a few for a winter setup given the typical uncertainty with thermodynamics. Listed below...
#2: 2/24/01 - deadly Pontotoc, MS F3 and several other strong tornadoes
#4: 3/1/07 - outbreak with Enterprise and Millers Ferry, AL EF4s and Americus, GA EF3
#6 2/17/08 - Prattville, AL EF3
#8: 1/10/08 - Caledonia, MS EF3 and several other strong tornadoes
#10: 1/20/88 - F4 in MS and a long tracked F3 starting east of Memphis
#12: 1/17/99 - Bemis/Jackson, TN F4 and several other strong tornadoes
#13: 1/24/97 - Murfreesboro, TN F4 and Tuscaloosa, AL F2
Don’t forget Cape values do not have to be very high at all this time of year! Cold season events do not require thatHonestly not impressed by CAPE values at this point. First sniff of the NAM came in even less than the GFS. Think a forced squall line with damaging winds, maybe a few embedded tornadoes in the most likely outcome.
Exactly ... there some pretty nasty analogs in cips ... Andy eluded to... most those events were not cape either.... cape is something a lot time are under done on global models .... that could change even.... still early ....Don’t forget Cape values do not have to be very high at all this time of year! Cold season events do not require that