Severe WX Severe Wx Outbreak March 1st- 3rd, 2023 - Southern States, MS/OH/TN Valley

[ashtonlemleywx]

I've had that Van Halen song from Twister playing in my head while reading this thread.

March is coming in like a lion guys. The Deep South in March/April is a mystical place.

 

[Clancy]

12Z run of the GFS showing less instability over the area, so if that sticks around it could potentially serve as a limiting factor. Shear is absolutely mental though.

 

[ashtonlemleywx]

Honestly I'm not even going to look at the GFS this time just because it shits the bed and then rolls around in it so often.

Euro, NAM, and HRRR are the only models I'm focused on.

 

[Clancy]

Honestly I'm not even going to look at the GFS this time just because it shits the bed and then rolls around in it so often.

Don't be too mean to the GFS it tries its best haha

 

[Former Member 1430]

I can’t keep but going back to something James Spann mentioned following the April 27th event…. If you have an excessive amount of shear and not enough instability the updrafts will get ripped apart. You can have everything lined up perfectly and end up with a non event because the updrafts are torn to shreds. Somehow this feels like that could indeed be that type of situation in my view.

 

[Taylor Campbell]

Last night’s EURO control of MUCAPE.

 

[UncleJuJu98]

I can’t keep but going back to something James Spann mentioned following the April 27th event…. If you have an excessive amount of shear and not enough instability the updrafts will get ripped apart. You can have everything lined up perfectly and end up with a non event because the updrafts are torn to shreds. Somehow this feels like that could indeed be that type of situation in my view.

Definitely, I'm not sure if you can find a exact value but usually around 2500 or so and above will do it. Maybe even 2000. No doubt will have a chance to reach near that if the euro is right

 

[JPWX]

I realize this might be too bold but here's my early assessment of the threat late next week. I will adjust this as we get closer in.

 

[tennessee storm chaser]

I can’t keep but going back to something James Spann mentioned following the April 27th event…. If you have an excessive amount of shear and not enough instability the updrafts will get ripped apart. You can have everything lined up perfectly and end up with a non event because the updrafts are torn to shreds. Somehow this feels like that could indeed be that type of situation in my view.

correct, the euro been pushing that type cape into southern tn... gfs is lacking in cape thus far... see how the euro has it soon

 

[Timhsv]

based off the euro alone, with that bomb of a system, wouldnt suprise me if a secondary slp develops further south. something watch out for future models runs that would even back winds even more

Absolutely. Reinforcement of vorticity even more so at 0-1km. I mean we all realize what we're looking at still at this range, but, if the TREND continues of coarse on all models, then we're in real trouble if the boundary layer instability is there, and that projected warm sector attm looks huge. These long range solutions are contentious lately to say the least thou.

 

[UK_EF4]

Definitely, I'm not sure if you can find a exact value but usually around 2500 or so and above will do it. Maybe even 2000. No doubt will have a chance to reach near that if the euro is right

I think more like 1000-1500/j/kg can often be enough even in extreme shear. There are quite a few events on torarchive where there were violent tornadoes produced in 1000j/kg of CAPE and large, extreme, looping shear profiles. Even March last year had a couple of discrete sups ahead of the line which were probably more like 500-1000j/kg. That's really pushing it though. Though that being said it is something I would probably need to do more research on.

 

[Austin Dawg]

I realize this might be too bold but here's my early assessment of the threat late next week. I will adjust this as we get closer in.

Take Monroe county out of that please.

 

[JPWX]

Take Monroe county out of that please.

I would love to and I wish I could.

 

[Taylor Campbell]

The EURO has a very expansive warm sector with low 60 dew points in lower Ohio, low to mid 60s throughout KY, and much of Alabama is in the upper 60s with a large area of 70s across the southern half.

 

[NorthGaWeather]

I can’t keep but going back to something James Spann mentioned following the April 27th event…. If you have an excessive amount of shear and not enough instability the updrafts will get ripped apart. You can have everything lined up perfectly and end up with a non event because the updrafts are torn to shreds. Somehow this feels like that could indeed be that type of situation in my view.

Yes and no. It really depends on each circumstance. Even in events where you have meager instability and updrafts are being sheared downstream, you can have a cell or two take off and produce tornadoes.

There are several good papers out there concerning HSLC environments. Here is one regarding simulation of those environments.

Dynamics of Simulated High-Shear, Low-CAPE Supercells

Abstract High-shear, low-CAPE environments prevalent in the southeastern United States account for a large fraction of tornadoes and pose challenges for operational meteorologists. Yet, existing knowledge of supercell dynamics, particularly in the context of cloud-resolving modeling, is...

journals.ametsoc.org

 

[JPWX]

The 12z Euro isn't as deep with the March 3rd system as previous runs, but still. A 981mbar low would still cause significant problems.

 

[GTWXAlum]

12z goofus says winter isn't over for the south in this time frame

 

[JPWX]

12z goofus says winter isn't over for the south in this time frame

O my! I just looked. It's 93 all over again. Lord. As much as I would love to see it snow, I'm sticking with a severe weather threat.

 

[UncleJuJu98]

Even though the GFS is a outlier, I wouldn't discount it's solution, big jumps are to be expected but what sticks is the question, the ensembles are interesting at the moment to say the least, the euro ensemble's have taking a side to a more eastward ejection, but it's a fluid situation lol

 

[warneagle]

I've had that Van Halen song from Twister playing in my head while reading this thread.

March is coming in like a lion guys. The Deep South in March/April is a mystical place.

If you're gonna do that at least put on "Child in Time" instead of Van Hagar.