American Darian Stevens took second place with 85.4 points while Grete Eliassen, also of the U.S., won bronze with 83.4.
Nikki Blackall of Barrie, Ont., was sixth.
Howell said she was able to stick to her routine despite slow conditions on the track following snowfall Friday night and Saturday morning.
"I was actually lucky enough to be able to stick to the run that I wanted to do and thankfully, the speed was OK and I landed on my feet," the 19-year-old said.
Up next for Howell is a week off for the holidays before getting right back to training for the next Grand Prix event in Breckenridge, Colo., in January.
"I just want to focus on progressing and making sure I'm having fun and doing what I love," Howell said. "It seemed to work today so all is good."