Skip Talbot
EF5
Friday looks like a fairly potent severe weather setup across the plains. The trough, which is just nosing into the plains on Thursday is forecast to be well established over the plains warm sector on Friday. Moisture advection looks to continue throughout the period, with dewpoints into the low 60's extending across a much wider warm sector than the day before and as far north as central Iowa.
I see a couple of targets here just looking at this morning's run. The first is up in southeast Nebraska, where the NAM is showing a small surface low. Lift should be enhanced and winds better backed in that vicinity resulting in sort of a triple point play. With moderate instability over 2000 J/Kg and a 70 knot shortwave ejecting over this area by mid afternoon, shear and instability combinations should be very favorable for large supercells and maybe a few tornadoes.
http://www.twisterdata.com/data/mod..._221_2012041012_F81_DPTF_2_M_ABOVE_GROUND.png
http://www.twisterdata.com/data/mod.../10/12/NAM_221_2012041012_F81_WSPD_500_MB.png
The dryline extends in a northeast to southwest fashion down to north central Oklahoma where it goes more southerly. That would be my next target. The winds will be better backed along the dryline there, and the midlevel flow more perpendicular allowing storms to get off the dryline and more into the warm sector. Storms speeds might be a little more manageable and coverage allowing for more discrete activity as this area is a bit more removed from the stronger speed shear and forcing to the north.
Curiously the cap, is forecast to erode very early in the day across the southern portions of the warm sector. The morning NAM has a huge squall line blowing up by mid afternoon and the northern end of the target area firing later. If that's the case, I'd probably lean on the NE end of the setup where instability and directional shear will be in a bit of a better combination. Otherwise, I'd say an area from Wichita into northern OK has an awesome veering wind profile and surface pattern for discrete supercells coming off in the dryline. If early activity doesn't botch the setup later in the afternoon and evening, that might be the place to be. Either way, the cap looks to be wide open by afternoon and with the large amount of lift from the established trough, this should be much more of a widespread event than Thursday.
I see a couple of targets here just looking at this morning's run. The first is up in southeast Nebraska, where the NAM is showing a small surface low. Lift should be enhanced and winds better backed in that vicinity resulting in sort of a triple point play. With moderate instability over 2000 J/Kg and a 70 knot shortwave ejecting over this area by mid afternoon, shear and instability combinations should be very favorable for large supercells and maybe a few tornadoes.
http://www.twisterdata.com/data/mod..._221_2012041012_F81_DPTF_2_M_ABOVE_GROUND.png
http://www.twisterdata.com/data/mod.../10/12/NAM_221_2012041012_F81_WSPD_500_MB.png
The dryline extends in a northeast to southwest fashion down to north central Oklahoma where it goes more southerly. That would be my next target. The winds will be better backed along the dryline there, and the midlevel flow more perpendicular allowing storms to get off the dryline and more into the warm sector. Storms speeds might be a little more manageable and coverage allowing for more discrete activity as this area is a bit more removed from the stronger speed shear and forcing to the north.
Curiously the cap, is forecast to erode very early in the day across the southern portions of the warm sector. The morning NAM has a huge squall line blowing up by mid afternoon and the northern end of the target area firing later. If that's the case, I'd probably lean on the NE end of the setup where instability and directional shear will be in a bit of a better combination. Otherwise, I'd say an area from Wichita into northern OK has an awesome veering wind profile and surface pattern for discrete supercells coming off in the dryline. If early activity doesn't botch the setup later in the afternoon and evening, that might be the place to be. Either way, the cap looks to be wide open by afternoon and with the large amount of lift from the established trough, this should be much more of a widespread event than Thursday.