04/20/05 FCST: South/Central/High Plains

[Scott Lincoln]

As of this time, I dont think your "high risk" is warranted, Nick. There is a cap over almost all of nebraska, except for eastern. The whole state has pretty much been covered by cloud cover. The helicity at the low levels may be increasing, but isn't very close to high risk material. I can definitely see the threat for a few isolated tornadoes near the Kansas/Nebraska border, where there has been more sunshine and also lies a weaker cap. The storms will have a hard time forming much north of southern nebraska... even if they did, the LFCs near the front are not very great either.

 

[Mike Johnston]

A wide view of the 500mb contours appears to be showing signs of the long-promised ejection, with 60 kt over the four corners and 30kt winds encroaching on TX panhandle. Whatever in the way of surface features are out there on the western horizon of the plains - peeping tom lows, etc. - may finally be steered through over the next 24 hrs. ICT hazardous outlook summed up this evening well:

IF ANY
STORMS OCCUR THIS EVENING, THEY WILL LIKELY BE SEVERE WITH LARGE HAIL AND DAMAGING WINDS.

, with the keyword being "if" IMO. Still look for the main course tomorrow, but perhaps a good appetizer this evening for our friends peering out on the dryline.

 

[Jeff Snyder]

Well, TCU rapidly buliding along the dryline from Beaver County OK to near Pampa to just east of Plainview. In fact, the latest vis satellite shows one storm going up (presumably breaking the cap) in the far eastern OK panhandle just west of Laverne, with another storm going up immediately northeast of Plainview. MCD stated WW to be issued soon, and the strong TCU support this. Currently mesoanalysis on SPC site indicates the best instability of the season so far over northwestern OK with 4000-4500 sbCAPE, south-southwestward into western north Texas with >3000 j/kg sbCAPE. Shear is pretty weak, though southeasterly surface winds in western north Texas are creating a favorably-veered low-level wind profile. Despite this, weak deep-layer shear will probably preclude much of a sustainable mesocyclone risk.

EDIT: LOL Just as I sent that, new blue box came across from eastern TX panhandle and western OK. Hail to 4"... yowsa's... I certainly would like to see a nice supercell now, especially given that the only stuff I've seen this year have been in 1000 CAPE crap... What I wouldn't give to see rock-hard convection. Well, I'd head out from OUN if we had another 10-15 of deep-layer shear (20-25kts is too measely for me w/o a good boundary for a storm to anchor on)...

 

[Glen Romine]

Well, I'd head out from OUN if we had another 10-15 of deep-layer shear (20-25kts is too measely for me w/o a good boundary for a storm to anchor on)...

Effective shear closer to 30 knots - which combined with that much CAPE - a multi-cell supercell hybrid certainly is plausible.

http://www.spc.noaa.gov/exper/mesoanalysis/s1/eshr.gif

Further, there does appear to be a boundary:

http://www.spc.noaa.gov/exper/mesoanalysis/s1/3cvr.gif

I'm not sure a trip to Medicine Lodge wouldn't be worth it if you have the time.

Glen