4/21/07 FCST: OK / KS / TX / NE

[Jeff Snyder]

Billy the thing that I really find interesting is that on 3/28 a lot of chasers stayed home because they thought the same thing as many are saying right now, STORMS WILL GO LINEAR. Well they sure didnt and a significant tornadic event unfolded. I think tomarrow is going to be a big day even if a squal line forms.

One of the key distinctions between tomorrow and 3-28 is that >60F dewpoints extended across the TX and OK panhandles, northward to west-central KS. In addition, and partially related to the better moisture, CAPE on 3-28 was almost twice what is forecast tomorrow. Archived SPC Mesonanalysis from 3-28 indicates >3000 j/kg from southwestern Nebraska all the way to western Texas, with pockets of >3500 j/kg CAPE. Tomorrow, models are consistent in forecasting 1000-2000 j/kg. With higher Tds and considerably greater CAPE, I would much prefer to chase 3-28 again than chase tomorrow.

Of course, that's not to say I'm sitting this one out, since I'm not. But, I just wanted to point out a couple of important distinctions between Saturday's forecast and the 3-28 tornado event.

 

[Bob Schafer]

Initiation will be 20-21Z. No high risk. By the time storms get E of 27, tornado risk will be mostly over.

 

[Joey Ketcham]

I wish dew points would be a little higher and wish directional shear was stronger, but I can't pass up a MDT risk day on a Saturday in the Texas panhandle.

I will be leaving in the next hour to pick up Russel Parsons and Chris Wilburn and we'll be heading between Lubbock and Amarillo and wait for storms to intiate along and ahead of the dryline.

Good luck to everyone else that'll be out and hope to see you out, we will be in my white Expedition.

 

[Dan Robinson]

Tornadoes look like a lock tomorrow. The key will be targeting far south enough to avoid the linear mess. If I were chasing, I would start 50 miles south of Lubbock, maybe even further south around Lamesa. That's taking a chance on not seeing a storm, but a better bet on a long-lasting isolated cell.

 

[Ray Walker]

Jeff, yes I know that dewpoints were in the 60's on the 28th and that cape was higher all I was pointing out was that everyone thought that the storms would go linear and they didnt. I think today is going to possibly be the same way, storms remaining isolated longer than what everyone thinks.

 

[Craig Maire II]

Today

Sitting in Liberal Kansas right now outside of a motel, after a 12 hour drive and not much sleep (didn't get a motel room) I feel like crp and sure hope that some discrete sups develop later today after 4pm, a tornado or 2 would be great but I'll settle with large to very large hail and storm structure I am hoping that the sharpness of this dryline and the shear/dynamics of this system will make up for the lower to possibly mid 50 DPs that should be in the area today.

 

[Michael P. Morris]

Just finished looking over some BUFKIT data, and I am now favoring the area between Childress and Tulia, Texas for most likely discrete/tornadic development. Check out this sounding valid for 0Z --> http://res.ocs.ou.edu/~mmorris/9356.GIF

Looking at the soundings on the Texas coast, it looks like they had pretty deep moisture at Corpus and Brownsville, though it may be a little late in the game for that to factor in today, but we shall see. There are already mid-50s and a couple of 60+ dewpoint observations in Central Texas which may get there in time for initiation, which I expect around 21Z.

Currently, I believe that the best targets will be further south as the cells will have slightly more veered mid-level flow as well as stronger moisture. As Alex mentioned, this morning's NSSL-WRF produces several discrete storms which bodes well for significant tornado opportunities. We will be packing up shortly and heading off to Childress.

 

[Amos Magliocco]

The link I normally use for the 4k WRF didn't update last night:

http://wwwt.emc.ncep.noaa.gov/mmb/mmbpll/cent4km/v2/

Is there an alternate?

My target today isn't too originial, invof LBB perhaps south where shear vectors are slightly more normal to the dryline. Without the extensive clouds I'd worry about dewpoint depressions but not so much today. Looks to me from the vapor loop that the upper low is coming in slightly south of the last night's WRF prog, not much.

 

[Jeff Snyder]

The link I normally use for the 4k WRF didn't update last night:

http://wwwt.emc.ncep.noaa.gov/mmb/mmbpll/cent4km/v2/

Is there an alternate?

Try the 4.0km NSSL WRF run --> http://www.nssl.noaa.gov/wrf/ ... That run shows initial linear mess, but then breaks up convection the linear mess into discrete cells by 0z.

You can also try the 3.0km WRF-ARW run --> http://wrf-model.org/plots/realtime_3kmconv.php ... Like the model run to which you linked, however, the 00z/21 run isn't available (yet?).

That's the WRF convection trifecta, as I call it (the run on the EMC site, the run on the NSSL site, and the ARW run on the wrf-model site, which is actually run by NCAR, I believe).

 

[Donald Giuliano]

Hmmm, not sure what to think this morning. The 12Z RUC is mixing out moisture like crazy near LBB, but looking at morning soundings I rather question that. Also, there are hints it could be better further north now (especially if you believe the 06Z HIRES WRF runs on NCEP). What to do, what to do. Probably will be heading in the direction of AMA, and reevaluating from there.

 

[rdale]

The link I normally use for the 4k WRF didn't update last night

You hit it too early as it's there now... That's the only web display - you can get the raw GRIB2 data and run it through WinGridds or GEMPAK and avoid the hassle.

It's got discrete cells forming by 22Z over the panhandle region, transitioning to a line over OK/KS after midnight.

 

[David Drummond]

Please keep in mind that posts stating where you are and were you are going without your commentary on the meteorological situation as to why you are there or are going somewhere are not appropriate for the FCT thread and will be deleted. And most certainly the complaints and directive to other chasers as to how they are to behave are not appropriate for this thread.

 

[Rich Thompson]

I extrapolate the srn AZ shortwave trough into the extreme wrn TX Panhandle by 00z, with the belt of ascent over the central Panhandle by then. As Donald G. mentioned, the 12z soundings don't look too susceptible to mixing at DRT/MAF/AMA, and I expect mid-upper 50s Tds to be maintained across the Tx Panhandle today. However, the cap is fairly strong (convective temps in the mid-upper 80s), thus it seems that storms won't be able to form much away from the dryline. Lee cirrus shouldn't be a problem today and the stratus is already eroding from SW-NE, so surface temperatures will likely warm to 80-85 F west of I-27 by mid afternoon (esp. S of I-40).

T-Td spreads will be a little high, but that shouldn't be enough to eliminate any tornado threat with discrete storms. The newer model runs, plus last night's 4 km WRF runs, show a little less tendency for linear convection during daylight, and that may work out with the reasonably strong cap in observed soundings this morning.

I'd set up shop in a spot with good data coverage along I-27 from Canyon to Plainview by 20z and hope to get a discrete storm in the better road network near and just west of the interstate from 21-23z.

Rich T.

 

[Jason A.C. Brock]

Ill try to see if Im worthy of posting anything of any substance fand as smart as everyone else.
I like the area outline fom Thalia to LBB to Childress. Dewpoints may be higher there but only slightly . looking SE towards ABI there are some at least some mid 50s dew. This area may have better proximity to the jet as well as things should remain a little more isolated for a little longer perhaps. Not anything magical but its there. I also notice the models are leaning a little more towards the AMA area and keeping things towards Lubbock wither mixed out or maybe even capped off a tad.
I still think Plainview will be a nice spot so that one can go North Or South or East. It will be a chore going around the Canyons as well.
Everyone have a great day and chase your hearts out. We will jsut have to see SPC storm reports tonight to see what went right and what went wrong.
Care Bear Kisses and Rainbow hugs!
Everone be safe

 

[Brian Stertz]

Sitting in the Plainview TX library right now pouring over the data and have seen the main dynamics of this strong system will coincide nicely with a dryline bulge across extreme SE Colorado, SW Kansas, W/C Oklahoma Panhandle and into the NW/NC Texas Panhandle. Am shifting my original target north and Rich/Ryan Thies and I are soon northbound from Plainview TX to the N. Texas Panhandle. The handwriting is on the wall fror tornadic supercell potential after 5pm today. Looks to me as though areas south of Dumas TX on the dryline may not benefit from the cap breaking support from the wave that will move into the NW Texas Panhandle and SE Colorado by evening.