A well advertised severe weather event is set to unfold today across the southern plains, namely portions of Oklahoma and southern Kansas. Severe thunderstorms are currently ongoing across portions of eastern and southeastern Kansas. These storms formed along a stalled boundary draped across southern Kansas then arching northward toward Missouri/Iowa, while a dryline stretched from south central Kansas through western Oklahoma.
The position of these two features will be critical in tomorrows severe weather outcome. Preliminary evening data suggests that the frontal boundary is going to sag further south than expected, with previous data suggesting it may reside near I70, whereas evening data suggests somewhere in the vicinity of the Oklahoma/Kansas border is more likely. Personally, I feel a compromise between the two is more likely, after analyzing soundings north of the front, seeing continued mid level height falls, and no clear signs for substantial overnight convection, I would seem to think the front would have to lift north to at least Wichita, KS, to possibly even Hutchinson, KS.
During the day is when things get tricky! There looks to be a substantial wave of energy that is preceding the main upper level disturbance. This could set off thunderstorms earlier in the day near or before noon. These storms would likely develop in the vicinity of the dryline/front intersection in northern Oklahoma/southern Kansas. These storms would move quickly east northeast. They may pose an initial threat for large hail and damaging winds, though its possible the tornado potential with these storms may increase slightly as they move into far eastern Kansas and Oklahoma in the later afternoon hours. These storms would be much less likely to produce significant tornadoes than any storm that forms later (next paragraph).
The main upper level energy will arrive in the mid afternoon and the real show will get underway. There will be some influences, probably an outflow boundary, varying frontal positions, etc, from morning convection, but the dryline/front/potential outflow intersection will likely be the first focus for initiation of the “second round of storms”. There are substantial differences with the dryline location in the models, but given current observations, I believe it will setup well west of I35. The RAP model, which tends to over mix moisture, has it becoming rather diffuse, but with moisture already in place, and deeper moisture on the way, I think the model is overdoing it. My best guess for “second round” initiation point would be from Anthony, KS to Cherokee, OK. From that point, additional storms may form down the dryline into Oklahoma. It should be mentioned again that while storms today will likely produce severe weather, the threat will not be incredibly widespread.
Once these storms form, it is likely (depending on ultimate surface feature evolution), that they will have substantial moisture and instability to work with to produce significant severe weather. Background soundings and shear profiles are very supportive of large hail. In addition, if winds can stay backed (southeast) through the afternoon as the surface low deepens, then a threat will exist for tornadoes. Some of these tornadoes could be strong and potentially longer lived. Any storm that can be near the triple point, where moisture is likely to pool, as well as any residual outflow boundaries from morning storms, will have the best chance to produce significant tornadoes.
I will be out chasing today. My preliminary target is Manchester, Oklahoma. I think the best potential for tornadoes will be storms near the triple point. I also think there is a secondary risk of decent supercells along the dryline to the south southwest as well, in western Oklahoma.