Skip Talbot
EF5
Sunday is shaping up into a very impressive setup with what looks to be a widespread severe weather outbreak across the MO and MS river valleys.
The first thing that really catches the eye is the very impressive 90 knot (some earlier runs were over 100 knots) 500 mb trough ejecting over a very large warm sector with dewpoints forecast in the 60's from northern WI down through LA. With little capping left by mid afternoon, dynamic forcing from that very impressive jet accompanied by lift along a dryline extending from Sioux City down to NE TX, expect an early to mid afternoon initiation and very widepread storm coverage. Storm mode might be questionable with many hodographs across the region showing huge straight lines. The 12z NAM is showing quite a bit better directional shea than the GFS, and regardless of the straight line hodos, all modes of severe weather look probable across the warm sector given the excessive shear profiles.
Unfortunately I still don't see Sunday as a very favorable setup for chasing, even if it is favorable for a severe weather outbreak as many high risk type setups are. Even though there is some veering between the 850's and 500's which could support some right turning supercells, the 90 knot 500's and 850's approaching 50 knots will lead to very, very fast storm speeds. And given the NNE storm motions, it may very well be impossible to keep up with these storms. Initiation also looks to occur over the very difficult terrain of MO, AR, and eastern OK. With widespread storm coverage, bagging a tornado may be kind of a crapshoot as well with supercells mixed in with clusters and bowing line segments. Right now I'd probably target western IA and get on storms early while they're discrete, where the terrain and road network is a bit more manageable, forecast instability is higher, and where the 850's back a little bit more for more favorable directional shear. It'll probably be more of a point intercept rather than a chase too.
The first thing that really catches the eye is the very impressive 90 knot (some earlier runs were over 100 knots) 500 mb trough ejecting over a very large warm sector with dewpoints forecast in the 60's from northern WI down through LA. With little capping left by mid afternoon, dynamic forcing from that very impressive jet accompanied by lift along a dryline extending from Sioux City down to NE TX, expect an early to mid afternoon initiation and very widepread storm coverage. Storm mode might be questionable with many hodographs across the region showing huge straight lines. The 12z NAM is showing quite a bit better directional shea than the GFS, and regardless of the straight line hodos, all modes of severe weather look probable across the warm sector given the excessive shear profiles.
Unfortunately I still don't see Sunday as a very favorable setup for chasing, even if it is favorable for a severe weather outbreak as many high risk type setups are. Even though there is some veering between the 850's and 500's which could support some right turning supercells, the 90 knot 500's and 850's approaching 50 knots will lead to very, very fast storm speeds. And given the NNE storm motions, it may very well be impossible to keep up with these storms. Initiation also looks to occur over the very difficult terrain of MO, AR, and eastern OK. With widespread storm coverage, bagging a tornado may be kind of a crapshoot as well with supercells mixed in with clusters and bowing line segments. Right now I'd probably target western IA and get on storms early while they're discrete, where the terrain and road network is a bit more manageable, forecast instability is higher, and where the 850's back a little bit more for more favorable directional shear. It'll probably be more of a point intercept rather than a chase too.
