05/10/09 FCST: TX

[Bill Schintler]

Chase Target for Sunday, May 10

Chase target:
Andrews, TX (32 miles north of Odessa).

Timing and storm mode:
Isolated high-based storms will fire after 7 PM CDT. While significant severe WX is not expected, isolated supercells may provide photogenic storm structure.

Discussion:
The recent zonal mid-level flow will give way to low-amplitude ridging over the central Plains and Rockies as an upper-low pushes slowly S in the Pacific and troughing increases in the WRN CONUS. Further E, low-amplitude troughing will shift SLY E into the Atlantic. At the SFC, return flow will increase along the WRN extent of the trailing CF over WRN TX. Flow at the SFC will remain weak along with a lack of sources of focus. Winds will switch back to the SE as the front washes out, with a resulting upslope component. Capping will be strong, with a stout inversion at 800mb beneath steep mid-level lapse rates approaching 9C/km, as noted on FCST soundings. Additionally, LLVL clouds will persist along and N of I-20 in TX throughout the period; resulting in differential heating across the boundary. Isolated storms should fire as assent from a subtle S/WV increases after 01Z. SFC-3km hodograph curvatures will increase after 02Z as an H8 LLJ strengthens to 25 kts.

- Bill
KD0DJG
www.twistertoursusa.com
9:15 PM CDT, 05/09/09

 

[Michael Thompson]

Nice brave call Bill, I actually was looking at GFS a couple of runs back when it started hinting towards this set up and had penciled in Hobbs, NM.

WRF/ETA has now come on board and in anything is slightly more promising with a tongue of CAPE aligned to the front range (if that is right right term in NW).

Worries and there a few - CAP strength especially with WRF is quite significant and 700mb temps are around 12C at best, but we do have upsloping of surface winds to consider and the altitude itself will help break CAP.

My attraction to area is exactly the same as yours - photogenic isolated storms.

 

[Jeff Passner]

I'd go south of there... dew points are in the 40s and Midland sounding shows almost no moisture except in a layer about 2000-3000 ft AGL. You might get on the north side of the Big Bend region and hope the cap can be broken. Del Rio sounding shows good moisture, but winds are very weak. I'd drfit to Fort Stockton and see if anything can happen. The area is beautiful in there but roads are limited. However, if a storm does form you should have good visibility and you might get that supercell you are looking for. Too bad the winds are only 15 knots at 500 MB but you do have a shot of a good storm.... Unless the cap holds.