A broad brush approach to today would suggest central Kansas as a target but, of course, it's a pretty big area! To that end, much closer scrutiny is (as always!) required. Some models (e.g. RUC) push a small dry-line bulge in from the west through the day - it is hard to know whether something like this will actually happen, especially in the absence of major upper forcing. Even so, with a fast SW flow aloft, mixing west of the dry-line would suggest this flow reaching the surface over western Kansas and helping to bulge the dry-line eastwards. Other models, such as the ECMWF, don't really do this, although this is still the hint of a slight push eastwards. The one more general consensus seems to be that the best chance of breaking out precip is somewhere in the line from Hays/La Crosse kind of area, although anywhere down the dry-line could see an isolated supercell develop.
This evening, low-level flow will increase further as the low-level jet cranks up. Instability remains quite high, including low-level instability. A window may exist for a strong tornado this evening as this occurs, with storms tending to keep going into the night as the upper trough moves closer.