The Hornets (8-11, 4-6) were trailing by one when a double technical foul was called on Weber State, giving Mikh McKinney four free throw attempts. McKinney, who finished with 30 points, sank all four to lead 75-72 with seven seconds left.
Weber State (11-7, 8-2) tied the game as Davion Berry sank a contested 3-pointer with less than a second remaining. Garrity corralled the ensuing inbounds pass and swished it from Weber State's 3-point line.
Garrity finished with 13 points and Eric Stuteville had 14 with nine rebounds.
Berry led the Wildcats with 29 points, Kyle Tresnak had 20 and Jeremy Senglin added 16. Joel Bolomboy pulled in 15 rebounds.
Weber State saw its six-game winning streak snapped.
Click here to watch the incredible game-winning shot.