Tuesday April 20th Update
Models have backed off a bit on the severe weather potential for the Tri-State area with this next trough that begins to move in to the area on Wednesday afternoon/evening. I will be unable to chase this next storm, but I'm going to make a forecast as if I were going to chase this next system, just for kicks....
NAM paints a good amount of CAPE over north-central Texas with temperatures in the 70's and 80's and dewpoints in the mid 60s. This will be the area where thunderstorms will fire. However, wind shear will be farily limited Wednesday before the trough begins to move through the area on Thursday. Expect very little in the form of rotating supercells.
NAM shows a very nice and well defined Dryline that cuts through SE Colorado with dewpoints in the 50's. Moisture wraps around a developing low that sets up south of Pueblo, Colorado. Directional wind shear in this area looks fantastic for at least the potential for a few tornadoes. The bad thing is, a cap exist east of Lamar where some of the best directional shear, at least in Colorado. The cap looks to break between the surface low and Lamar, Colorado leaving a very narrow area for thunderstorm development. Due to the cap, models have showed very little in the form of QPF over this area. However, I feel this area should be watched closely, because if a storm were to develop in this area, it could be a very photogenic supercell.
The bulk of the activity looks to be southeast of Lamar in to Oklahoma and Texas. Dryline will set up east of Amirillo, Texas. CAPE of 2,500 - 3,00 j/kg exist along the Texas/Western Oklahoma border. Low level directional shear looks on I-40 along the Texas/Oklahoma state line. However, I would look at someplace slightly further north, perhaps along a line from Perryton, Texas to Woodward, Oklahoma. SFC - 500mb Bulk shear looks great in this area, with great directional shear at the surface. It also plays a great role as a potential convergence zone with a more well defined dryline in the area. Models also depict a good amount of 0-1km helicity in this area. Models show this part of the dryline fireing first.
So if I were chasing, my target would be Booker, Texas.
Closer to home.....
Although models have decreased the severe potential for the Tri-State area on Thursday, I'm not yet sold that nothing will happen. Dewpoints will be in the mid 40s across the area with CAPE values of 750-1150 in Weld county. Tornado threat is practically non-existant anymore with wind shear looking to unidirectional. Wouldn't suprise me if we do see a few storms become severe with large hail and gusty winds, as winds aloft are strong enough to keep rain and hail out of the updraft allowing storms to live a little longer, therefore becoming stronger.