Several potentially-tornadic supercells have occured this afternoon and evening. One potentially tornadic supercell has essentially dissipated in northern Kansas, while another is in the process of weakening in northcentral Nebraska. Both of these storms had nice low-level mesocyclones / couplets -- the northern KS storm was located far from any radars, so the lowest scans were still 10kft AGL. The nc NE storm produced a tornado a couple of hours ago, while other potentially-tornadic storms have been ongoing across eastern SD and sw MN. There was a very nice low-level couplet associated with a supercell south of Montevideo, MN, though I question whether this verified owing to a relatively stable near-surface layer. Otherwise, strong flow pretty much throughout the troposphere (25+ kts at 850mb and stronger above) has aided in relatively favorable deep-layer shear profiles for supercells. Capping looked like it was going to be an issue for convection south of the SD/NE border, though this capping was obviously overcome in some places.