Ryan Pilon, Russell Maxwell and Brady Ramsay each scored for Lethbridge (9-7-2), which scored four unanswered goals for a 4-0 lead.
Hunter Shinkaruk and Trevor Cox each replied for the Tigers (9-9-1).
Hurricanes goaltender Ty Rimmer made 27 saves for the win. At the other end of the ice, Cam Lanigan was chased from the net after allowing four goals on 28 shots.
Marek Langhamer came in and allowed one goal on 25 shots for Medicine Hat.