18Z NAM at FH054 remains quite interesting for Friday evening at FH054 with very strong low-level curvature in the forecast hodographs, a modest/breakable cap, and >5,000 j/kg MLCAPE in parts of S WI/N IL.
The surface chart appears to depict the reason for these enhanced hodographs as a sort of secondary surface low near the MS river, out ahead of the main one which it depicts over the IA/NE border.