No. 9 hitter Tory Lewis singled up the middle to score pinch-runner Whitney Hammond with two outs in the bottom of the seventh inning, in the winners' bracket.
The loss means the Huskies will play Sunday at 12:30 p.m. Pacific time against either Arizona State or Michigan.
After a harrowing night of severe storms in central Oklahoma, the World Series resumed, with four games scheduled, beginning with a pair of winners' bracket games between Tennessee and Washington and Texas and Oklahoma.
Those games had been scheduled for Friday night, but instead, at least six of the eight teams in the NCAA softball championship rode out the storms at the Cox Convention Center, which has an underground parking garage, and in the tunnels that connect it to hotels in downtown Oklahoma City.
"We could kind of tell throughout the whole week that possibly there was going to be this happening, so I think the whole team was mentally prepared for it," Washington coach Heather Tarr said. "You just deal with these things like any sort of team event that happens or any sort of adversity in the games. We just deal with it as a team and compensate and adjust and work together to stay together."
Ellen Renfroe (19-4) allowed two hits and struck out 10 for Tennessee, which will next face a team from the losers' bracket.
Tennessee (51-10) stranded 13 runners through six innings against Washington's Kaitlin Inglesby (23-8), leaving the bases loaded three times. In the seventh, Cheyanne Tarango reached on an infield single and Hammond ran for her.
Melissa Brown sacrificed Hammond to second base. Rainey Gaffin walked and Hannah Akamine lined out to Inglesby, who unsuccessfully tried to double Gaffin off first base. Hammond took advantage and raced to third base, setting up Lewis' game-winning hit.