2013-05-30 FCST: KS, OK, MO, TX

[Brian McKibben]

I figured I would get this started. Thurs looks to be better than Wed (which was kind of a let down) since the winds should have less veer-back. The cap doesn't look to be as big of a problem as previously thought. In fact the 00z NAM breaks out precip on the DL by 00z. The shear looks good with helicities above 200 m2/s2. If the CAPE is a little larger things could be explosive, but they are on the order of 2000-3000. Which is still great.

Central OK from I40 and north look to be a decent play.

Good luck to all and stay safe. Let's hope if there are tornadoes they stay out in the waving wheat and away from populated areas.

OKC 00z sounding:

 

[Brian McKibben]

Up to Mod risk now. 00z 4km SPC WRF has a storm north of OKC metro with a movement toward the ese. Will wait to see 12z run before sounding the alarm.

 

[Brian McKibben]

Just saw the 12z OUN sounding. Wow. I hope it doesn't look like that this afternoon with a little heating. Very impressive wind field.

 

[Chris Wilburn]

The concerns of yesterday are not really concerns today. By looking at the sounding you posted above Brian, it is nice to see a more traditional upper wind profile as compared to yesterday. Moisture will be more abundant today also, which will help with LCL heights. The bases were really high most of yesterday in the TX panhandle and SW OK with td spreads over 20 and even 25 in some places. That is one very strong low level jet. Also, with the 500mb winds not really fast this will help with storm speeds. Moisture, instability, and LCL heights will not be a deal breaker today. Of course, the more instability the better, but forecasted over 3,000 is a very good start. Hopefully we can get the directional shear to cooperate like it is forecasted to do. Also, that is some very nice 0-1 SRH values of over 400. I don't really see too many issues with today to be honest. Actually, I do have some concerns with NE OK as the WRF put some precip over the area most of the day and it's currently raining there now. Maybe the environment can recover and of course this may leave over a nice OFB to look for later today as I plan to. Good luck to everybody and stay safe!

 

[cstrunk]

The highest severe threat should be to the south of the current convection in southern KS and northern OK. The environment in central OK is already insane. Dewpoints are in the upper 60's and lower 70's, pushing CAPE above 3000 already. Shear is greater than 50 kts. Any isolated storm that fires this afternoon in Oklahoma will have ample opportunity to go crazy.

 

[Adam Atkins]

It's obvious the SPC has their hands full today with 3 mesoscale discussions out for E OK/MO, IL, and WI and a new tornado watch in WI. They haven't had the time to even get the discussion or watch out for C OK. The dryline has really tightened up in SW OK, south of I-40 and convection has fired before noon...unsurprisingly based on the 12z OUN sounding where the convective temp was only 74!

Juice is there and the wind fields will improve throughout the day as low levels back, mid levels veer and deep shear will increase. Mind storm motions today as they will be ESE/SE with right movers.

 

[chrisbray]

The wind profiles on the ILX sounding this morning look like a mess, at least on the upper half. Low level winds are pretty good though, which may help, and probably why they are discussing issuing a tornado watch in Illinois soon. Models show decent EHI in the area as the afternoon progresses to the evening. Seems like lots of fast moving lines, but I'll definitely be keeping an eye on this

 

[cstrunk]

Initiation has taken place northwest of Lawton. The cell is already severe-warned and has a track towards the OKC metro area. Keep an eye on this one.

 

[Jeff House]

Cell severe warned near Lawton may have to battle warming mid-levels. Let's hope so for the sake of OKC. On the other hand, it’s not that warm aloft relative to surface heat. Cell WNW of OKC Metro closer to OFB, which has finally stalled. Hope it roots after safely northwest of OKC Metro. Morning thinking, below, stands.

Strong jet max is somewhat straight; therefore, one might analyze the four quadrants. Oklahoma is in a "wrong" quad for enhanced lift, and Kansas is behind the OFB. Also got subsidence behind morning wave. On the other hand if it behaves like a curved jet max then OK will light up. Instability is high; some of that subsidence “neededâ€￾ early to reload the gun; and, low level directional shear will be good. The question is between: Right on the OFB closer to middle of jet max; or, first supercell south of OFB on DL for the more isolated play. OFB has shear but risk of cool pool. DL has instability but risk of wrong jet quad. Given slight UVV on models into all of Oklahoma, I slightly lean DL. One might hedge north though. Typically easier to correct south than to chase north. Good luck and be safe!

 

[Jeff Duda]

"Failure" modes so far:
-Initiation too early (lack of capping)
-Veer-back wind over much of OK with little shear magnitude above the PBL

Given the environment, I'm not surprised storms have struggled to organize and maintain themselves.