A little late to get a chance to look this over, but here is my guess(es). Two different areas capture my attention. The first, as has been well noted, is along the warm front / dryline intersection over northern KS. In particular, theta-E nose pointing toward just west of Hill City could certainly draw me toward that region. The down side of this choice is that it appears storm motions would have storms move northward away from the boundary - and toward that horribly cool and drizzly region in Nebraska. Yuk. 18Z update showing a pretty soft dryline up there though, so that is disappointing as well for dryline cells to kick off south of the warm front and then crossing as mature cells. The next best looking region could well be back around Childress. Pressure analysis at 15 Z and 18Z shows a E-W trough in this region intersecting the dryline, along with improving deep layer shear. But, mass convergence looks fairly weak and most of the diffluence was to the north, so the cap might be tough to break despite some indication of a 700 mb cold front sweeping toward the region. I probably would have went with the safer bet for convection in KS without any additional information to go on.
Glen
