Man, I can't help but have a very sour feeling about tomorrow, at least in terms of a significant tornado event... It just seems like the trough axis and vort max are too fast and/or too far east relative to the dryline. Where the best instability is likely to develop by mid-late afternoon ahead of the dryline, deep-layer shear profiles will likely be 30-40kts and low-level will be comparatively weaker. This would be fine if we had stronger instability, but 1000-1500 j/kg CAPE with 35kts 0-6km shear doesn't get me too excited. In addition, as others have noted, the 850mb flow is forecast to veer to southwest ahead of the dryline, which, per forecast soundings, advects in much drier air immediately above the surface. On the good side, sites like OKC END and ADM show better low-mid level lapse rates, but moisture quickly decreases above the surface in some locales. I've chased in those types of environments before, and I've tended to see little but struggling TCu that can't do much owing to mixing. So, along the dryline by mid-late afternoon, there'll likely be marginal deep-layer shear and poor low-level moisture profile, despite the relatively larger CAPE. For example, look at the 00z
OKC forecast sounding from this evening's 00z NAM.
A little farther east (say near TUL CNU and MLC), the mid-level flow will be southwesterly as it will be downstream of the trough axis. However, models continue to indicate that poor instability will characterize these areas. Another forecast sounding --
00z TUL forecast sounding -- note the marginal instability and unimpressive low-level thermo profile. Of course, the low-level lapse rates will be almost entirely dependent upon extent of elevated convection and extent of insolation, but that's nothing that we haven't known for the past couple of days.
Looking through everything, I'm really torn. To the south, the
21z GLE sounding shows a pretty good thermo and instability profile, but that quickly shifts eastward by 5:30-6:30 pm. If you can stand the trees, LBR in northeastern TX looks good by 00z (
HERE). Logistics could be quite difficult in northern TX given storm moving quickly to the northeast and, as such, bringing the Red River into play. To the north of OKC, ICT doesn't look too bad, but mid-level flow weakens quite a bit and, subsequently, has relatively marginal deep-layer shear.
Looking at 0z model output, I'm find it extremely difficult to pinpoint a target at this time. Logistics are going to play an important role tomorrow given storm motion, and real-time data might be very helpful given possibility of scattered to widespread elevated convection and cloudcover that may require chasers to find the needle in the haystack. My current plan is to stick around OKC and hope that a target becomes more clear by noon. It could be a relatively early start; I wouldn't be surprised to start chasing at 18z in western OK and end up east of TUL by 0z. I'm not necessarily thinking it'll be a bust, but my concerns are mounting sufficiently to make me doubt a significant tornado event. Cloud-cover, elevated convection, early start of sfc-based convection, drying just off the surface moving over the warm sector, fast movement of trough axis (or at least the change from SW to W flow at 500mb) to the east of the dryline by early afternoon, etc. I want to play N of I40 given terrain considerations, but I also feel that the best shot for significant tornadoes will be S of I40, mainly in southeastern OK and northeastern TX. In my experience, N TX is fine chase territory W of Paris, but becomes progressively more tree-filled to the east of Paris. I've chased in SE OK a few times, but road options become quite limited (and very non-gridded) quickly, which could make the effort to follow a storm moving 45-50mph to the northeast futile.
EDIT: Perhaps it's a good omen that there are two very healthy supercells with hook echoes S of AMA along I27 right now!
