A Mexico woman died in a two-vehicle accident in Callaway County Tuesday afternoon. The State Highway Patrol reports that around 1:40, a car driven by 39-year-old Nicki Nation collided with the rear of a semi driven by 34-year-old Aaron Shirley of Fulton while both were westbound on Highway 54 at the intersection of Route T. Nation was pronounced dead at the scene. Shirley was uninjured.