Skip Talbot
EF5
I've been watching the models for over a week now to see if we're going to get anything chase worthy out of this big trough forecast to move on shore in the next few days.
The first real shot at a chase I see is Friday down in Texas, well before the trough arrives. At the surface, dewpoints >50-55 are forecast to move into the higher terrain of the west TX panhandle. Surface flow looks like it's going to be south-southeast. Although the surface flow isn't perpendicular to the caprock, the lift from the rising terrain, a sharp dryline, and a hint of an upper level disturbance might be enough to squeeze off a few storms in the panhandle. Strong surface heating and steep midlevel lapse should destabilize the area nicely with the 12z NAM plotting values over 2000 J/Kg SBCAPE across the panhandle into other parts of the southern plains.
There's a laundry list of issues with this setup, however. With the trough well off to the west still, it looks like we'll have issues with shear and the EML. The 12z NAM is showing small pockets of barely adequate deep layer shear. Without that trough we just don't have any upper level support. It's going to be real hit or miss for a storm finding a localized pocket of shear and updraft separation may be lacking as a result. Hodographs curve nicely with the veering with height, but are quite small. 1km SRH is almost non existent across the panhandle, which may hinder the tornado potential. An EML also appears to be in place. 12z NAM is showing modest erosion of the cap by 0z with rather small holes. Inhibition may suppress storms across much of the southern plains accept in isolated areas. Another major problem for tornadoes are the high dewpoint depressions and LCL's. Bases are going to be quite high, and with the lack of deep layer shear and SRH, storms may gust out and collapse before they can develop into supercells or lower their bases as cooling surface temps drop the LCL's in the evening.
Further to the northeast across NW OK and SC KS, a well defined dryline bulge is being plotted on both the NAM and GFS. This might be the focus for storm initiation in this area if the cap can sufficiently erode and there's enough upper level support. This area suffers from the same shear and dewpoint depression/LCL issues as well, however.
Right now, I'd watch Midland/Odessa to Lubbock for a shot at some photogenic but high based hailers, with a secondary target of Woodward, OK. You're going to need to get lucky with a burp of a disturbance in the midlevels, a localized boundary the models aren't resolving, or deviant storm motion to have a shot at a supercell that lasts for any sort of a decent time frame. I'll sit this one out as the distance doesn't warrant a trip for isolated storms struggling against weak shear and spreads that mitigate the tornado threat. It could be a photogenic day for a local play if you're in the right spot, however.
The first real shot at a chase I see is Friday down in Texas, well before the trough arrives. At the surface, dewpoints >50-55 are forecast to move into the higher terrain of the west TX panhandle. Surface flow looks like it's going to be south-southeast. Although the surface flow isn't perpendicular to the caprock, the lift from the rising terrain, a sharp dryline, and a hint of an upper level disturbance might be enough to squeeze off a few storms in the panhandle. Strong surface heating and steep midlevel lapse should destabilize the area nicely with the 12z NAM plotting values over 2000 J/Kg SBCAPE across the panhandle into other parts of the southern plains.
There's a laundry list of issues with this setup, however. With the trough well off to the west still, it looks like we'll have issues with shear and the EML. The 12z NAM is showing small pockets of barely adequate deep layer shear. Without that trough we just don't have any upper level support. It's going to be real hit or miss for a storm finding a localized pocket of shear and updraft separation may be lacking as a result. Hodographs curve nicely with the veering with height, but are quite small. 1km SRH is almost non existent across the panhandle, which may hinder the tornado potential. An EML also appears to be in place. 12z NAM is showing modest erosion of the cap by 0z with rather small holes. Inhibition may suppress storms across much of the southern plains accept in isolated areas. Another major problem for tornadoes are the high dewpoint depressions and LCL's. Bases are going to be quite high, and with the lack of deep layer shear and SRH, storms may gust out and collapse before they can develop into supercells or lower their bases as cooling surface temps drop the LCL's in the evening.
Further to the northeast across NW OK and SC KS, a well defined dryline bulge is being plotted on both the NAM and GFS. This might be the focus for storm initiation in this area if the cap can sufficiently erode and there's enough upper level support. This area suffers from the same shear and dewpoint depression/LCL issues as well, however.
Right now, I'd watch Midland/Odessa to Lubbock for a shot at some photogenic but high based hailers, with a secondary target of Woodward, OK. You're going to need to get lucky with a burp of a disturbance in the midlevels, a localized boundary the models aren't resolving, or deviant storm motion to have a shot at a supercell that lasts for any sort of a decent time frame. I'll sit this one out as the distance doesn't warrant a trip for isolated storms struggling against weak shear and spreads that mitigate the tornado threat. It could be a photogenic day for a local play if you're in the right spot, however.
