2011-05-19 FCST: CO/TX/OK/KS

[Andrew Stoller]

I was going to mention that Bill. SPC mesoanalysis already has 2,500 to 3,000 J of uncapped CAPE from Pratt southward into northwest OK and the sig tor is already 3 in south central KS. That actually has me concerned that everything will go up early and isolated discrete convection will not be the preferred storm mode.

 

[Derek Weston]

Holding tight for now in Hoisington KS. Idea is to play near the triple point up north. . . trying to resist the urge to move southward along dryline. Ought to have better low level shear in this area later today towards the warm front. . . though I have the concern that storms could become a bit more junky up here. Imagine we'll have quite a few chasers cruising the highway 281 corridor today.

 

[Jeff Duda]

There seem to be signs that initiation may take place soon in NW OK/far SC KS other than the CU field building. SPC mesoanalyses show very low LFCs in the area (below 1200 to 1000 m over a wide area of W OK and far SC KS), a pocket of upward motion in the 700-500 mb layer in W OK, and some decent mass and moisture convergence at the surface in portions of W OK and far SC KS, near the low center. Given that surface temps are now into the low-mid 80s in far NW OK and upper 70s in SC KS, and that the convective temp on the DDC sounding was only 80F, it's not too unreasonable to estimate that the convective temperature is about to be reached in that area. Thus, initiation may not be far off.

The good news in this early initiation is that many of the hi-res models are predicting two waves of discrete storms today in KS. One early in the afternoon and the second at or after 00Z a bit to the west.

 

[Chip Redmond]

At the moment, best mid level lapse rates along with highest bulk shear is along the warm front and near the triple point. 850 winds south along the dryline into OK are veering a bit and that is helping deter some potentially better low level shear and helicity in that region. This morning's DDC sounding seems to echo that as well vs the OUN sounding. As upper level support, 300mb streak begins to enter the region in the next hour or so, I feel the best location to be will be into central KS with much better tornado possiblities because of what I just mentioned when convergence increases at the surface. PW's are also much lower in the area of the triple point and this could actually help prevent hp messes. I supposed PW's aren't that bad over the entire region and classic will be the storm mode.

Chip

 

[Chris Vagasky]

KFDR showing convective initiation along the dryline along 287, just south of the Red River.

Just southwest of Quanah, already showing 60dBZ core, and supercellular appearance.

 

[Mike Johnston]

KFDR showing convective initiation along the dryline along 287, just south of the Red River.

Just southwest of Quanah, already showing 60dBZ core, and supercellular appearance.

Yeah and another area of potential interest between Medicine Lodge and Kingman, KS. W/ eroding CIN and surface moisture convergence, RUC is indicating initiation over the next hour or so in this general area. Radar already indicates some possible young cells trying to hatch. We should see a mesoscale discussion out pretty soon.

 

[Chris Vagasky]

MD out for Western Oklahoma, with a Tornado Watch due out soon.

 

[Jeff Duda]

Several consecutive HRRR runs have been showing a relatively slower moving supercell tracking NE right across the Wichita metro area late this afternoon. The storm has very high updraft helicity as it is going through town. Will have to keep an eye on that.

 

[Ryan McGinnis]

The initiation in TX right now is a bit worrying to me - the moisture has already advected so no problem there, but I'd hate to see a cirrus deck stick a fork in the day like last week.

 

[Chip Redmond]

I don't see the tops from those storms being an issue for new storms later along the dryline or even into KS as the tops are going to be directed to the east today.

Chip

 

[Michael Riedl]

The initiation in TX right now is a bit worrying to me - the moisture has already advected so no problem there, but I'd hate to see a cirrus deck stick a fork in the day like last week.

I am not too concerned about it at all, geographically it is a ways away from where the highest threat area looks to be near Central to North Central KS, and clearing is definitely quite good there and starting to get better.

 

[Jeff Duda]

The warm front appears to be pretty clearly delineated by a slowly northward-advancing line of cumulus stretching WNW-ESE across C KS right now with quite a bit of clearing forming NORTH of the front. Temps are already surging into the mid-80s in SC KS south of the warm front. However, as others have pointed out, surface winds are veered there, too, probably due to mixing of the PBL up to those 850 mb winds which are also veered (however, 925 mb winds are analyzed as SSE, so my mixing theory doesn't quite fit winds at that level...not sure why the veering is happening then unless there is a dryline bulge that isn't mixing out dewpoints yet). Low level winds are forecast to back to the south later on, so this should take care of that problem. However, until then, low level shear and convergence along the dryline may remain fairly weak.

EDIT: I see the Pratt ob just turned back to the SSE in the last hour. Medicine Lodge is still SSWly though.

 

[Michael Riedl]

Appears to be some agitate TCU going on West of Wichita. Hopefully it will get interesting here soon. Infact appears to be some returns in Kingman County from the ICT radar.

 

[Jeff Duda]

Thunderstorms are rapidly intensifying in SW OK now. Looks like 3 discrete supercells now exist moving northeast. They have quite high reflectivities, indicating large hail likely. Velocities aren't impressive right now, but that probably doesn't mean much.