Severe WX Severe Weather Threat 3/26-3/29, 2020

[TornadoFan]

 

[KoD]

There's some scary hodographs in West Illinois tomorrow. They don't look too bad until the line approaches and by then the forecast sounding is rain contaminated.

 

[Kory]

There's some scary hodographs in West Illinois tomorrow. They don't look too bad until the line approaches and by then the forecast sounding is rain contaminated.
View attachment 2626

Hmmm some slight backing at 500mb. Not sure that matters with everything else in place but it does begin to occlude by that time and that can mess up wind fields. Just something to keep in mind. Obviously a very potent set up.

 

[WesL]

Fun times out in Oklahoma and Arkansas -




Correction - Baseball sized hail now...

 

[bwalk]

Illinois ramping up for some severe weather

 

[TornadoFan]

Helicity tracks on the 00Z HRRR.

 

[Peter Griffin]

Helicity tracks on the 00Z HRRR.
View attachment 2628

Ugh not good at all

 

[Equus]

Day One outlook expands MDT and ENH somewhat and discussion mentions upgrade to High is on the table if trends look to support it nearer to event start. Pretty nasty day incoming.

 

[WesL]

Wow this hail would ruin your day.

 

[Equus]

With 95 hail reports - 27 of them 2"+ diameter hail - I'm a little shocked SPC didn't throw in a higher corridor of hail probs on the 20z; that's massive overperformance on a day that never went higher than slight (15/hatch hail) Very, very significant hail swaths today

 

[Kory]

Today is looking kinda messy on the mesoscale models. I don't think we get an upgrade after all.

 

[Kory]

I don’t think a single model had a complex of storms moving into Illinois this morning. That will certainly affect things.

 

[tennessee storm chaser]

Wouldn’t be surprised see spc go enhanced for mid south later today east ark west to north ms... lapse rates r crazy high with dew points pushing 70... wind damage will be nothing sneeze at. The threat that is

 

[Equus]

If that early mass clears as fast as it's looking like it might, there's probably still time to get sufficient destabilization before the main show arrives, but would certainly greatly reduce the chance of going high. Might even lay out some boundaries as it dies that could cause some trouble later.

 

[Kory]

If that early mass clears as fast as it's looking like it might, there's probably still time to get sufficient destabilization before the main show arrives, but would certainly greatly reduce the chance of going high. Might even lay out some boundaries as it dies that could cause some trouble later.

I think the problem comes in with the convection overturning a lot of the monster lapse rates (convection warming the mid and upper levels).

 

[Equus]

True, true. Always a fly in the ointment on day one. Killing the lapse rates might save a bunch of car windows and skylights though lol

 

[Equus]

Moderate maintained, and highly surprisingly they still say a 20z high is still in the cards depending on trends. Unusually aggressive wording from the normally pretty conservative SPC

 

[KoD]

Moderate maintained, and highly surprisingly they still say a 20z high is still in the cards depending on trends. Unusually aggressive wording from the normally pretty conservative SPC

Yup, sounds like they think it warrants a high risk but they don't know where to put it

 

[Kory]

I’m not the expert here. I just don’t see where this warrants a high risk....or even a moderate. The threat is lessening compared to some of those apocalyptic solutions of yesterday.

 

[warneagle]

Yeah I thought if anything they'd consider downgrading to an enhanced rather than going up to a high.