Weber State (22-5, 16-2 Big Sky) led 37-29 at halftime but the Lumberjacks used a 20-5 run to begin the second half capped off by a Gabe Rogers 3-pointer to give Northern Arizona a 49-42 lead with 8:32 remaining in the game.
Trailing 69-67 with 11 seconds left, Berry hit a pair of free throws to send it to overtime and the Wildcats scored the first seven points in overtime to hold off Northern Arizona (11-18, 8-10).
Rogers finished with 25 points while hitting six 3-pointers to lead the Lumberjacks. DeWayne Russell had 17 points, seven assists and six rebounds. Max Jacobsen finished with 17 points.
Weber State shot 47.3 percent from the field and was 19 of 23 from the free-throw line.
Former Kentucky guard Ed Davender, the only Wildcat with at least 1,500 points and 400 assists, has died. He was 49.
Guard Naz Mitrou-Long, whose 2015-16 season ended in December due to hip problems, has been granted a hardship waiver for the coming season, Iowa State said.
As the Sooners look to life without superstar Buddy Hield and his sidekicks, it's clear their unseasoned players will need to grow up fast.