I know there's a chance of really bad weather but 2011 bad? That was a once in a lifetime kind of event.
Last week's system never concerned me. This one does. This is a serious severe weather system with the potential for strong long track tornadoes across portions of MS, AL, southern Middle TN, and southern East TN. This is shaping up to be a deadly tornado outbreak across the south. I'd guess a likely SPC High Risk is coming for portions of MS/AL with tomorrow's Day 1 outlook.
~Severe Weather Outbreak~
Something to keep in mind is that the severe weather threat tomorrow is conditional. There is still some uncertainty regarding the timing and amount of instability in East TN. There will be a period of moderate to heavy rain in the morning, which could lower the risk for severe thunderstorms later on if the Sun doesn't come out.
Timing:
First round (scattered cells) in the afternoon into the early evening hours. Second round (line) in the late evening/early overnight hours.
Hazards:
Damaging winds in excess of 60 mph is the main threat. A few tornadoes are also possible, especially south and west of Knoxville. A strong tornado (EF2-EF3) or 2 can't be ruled out. Also, there is a threat for flash flooding in the southern valley and plateau.
Update:
The enhanced risk has expanded eastward some to now include all areas along and west of interstate 75.
I don't say this lightly. People will die today. This is a setup for an extremely dangerous severe weather event with strong tornadoes. I haven't seen a setup this favorable for tornadoes around East TN in quite sometime. We'll see how much destabilization we get this afternoon, but it appears we're going to get it with some partial clearing and huge warm air advection. I'd bring the moderate risk closer to Knoxville if I were SPC.
Please have multiple ways to receive watches or warnings and have a plan for a safe place to seek shelter if warnings are issued.
I never like comparing events because each one is so different in their own way. That being said, today's atmosphere is very similar to the atmosphere on 4/27/11 across portions of the TN Valley. The spatial extent is slightly different, but the amount of instability and shear will result in likely large tornadoes across portions of MS/AL/TN.How close to April 27, 2011 do you think this will be?
Overall hail threat isn't bad, but with any tornadic supercells, large hail will be likely. The strong rotating updrafts enhances the overall support for hail more than environmental instability would indicate. Same thing happened with the April 2011 event (didn't have any really impressive instability...no more than 1000 J/Kg).One difference that this system will have over the one in 2011 is that the hail threat won't be anywhere close as bad in East TN.