Tornado Central

There continues to be some potential for Wednesday, but the setup faces similar obstacles as the previous one (namely, questionable moisture and initiation). Last night's NAM was forecasting southwesterly 850mb across most of the southern plains, which was ushering in very warm and dry air just above the surface. Through the past few model runs, however, the NAM appears to have backed off this forecast, with the more recent 00z run backing the 850mb flow to SSW by Wednesday evening. There appears to be an opportunity for a rogue supercell in a relatively narrow zone of reduced CINH in northcentral Oklahoma (+/- 50-75 miles), as upper-50s Tds (and maybe even >60F) combine with 65-75F temperatures ahead of the dryline to produce ~1500 j/kg SBCAPE. Questions of initiation remain, as there remains some capping which may suppress convection until after dark. There is a hint of a lobe of mid-level vorticity swinging through the area near 00z, but the "big kahuna" hangs back until ~12z the following morning, so we won't have much DPVA to help out. It'll be a tough call, but that's relatively common for this time of year.

The NAM forecast sounding valid 00z/01 at OKC looks rather tempting: http://beta.wxcaster.com/cgi-bin/par...TION ID=_KOKC

It's important to note that the GFS is considerably less aggressive with moisture return, indicate pitiful moisture depth (and magnitude). If this verifies, I'll look back at this post and shake my head, for it'll feel silly to even consider chasing given the look of the GFS forecast soundings....