The 18-year-old earned a 72.12 in the short program and followed it up with a 139.57 in the free skate for a total score of 211.69.
Last year's U.S. junior champion, 15-year-old Polina Edmunds, won second place with a short program score of 66.75, a free skate score of 126.88 and a total score of 193.63. She, too, was named to the U.S. Olympic team.
Causing a bit of controversy, though were third- and fourth-place winners Mirai Nagasu -- 190.74 total points -- and two-time defending U.S. champion Ashley Wagner, who fell in her free program and finished with 182.74 total points.
Though she finished in fourth place, Wagner was selected to the women's Olympics team over Nagasu. Though its not a mandate, in previous years, the outcome of the Nationals competition has generally been used to determine the Olympics squad.
"I am at a loss for words right now," Wagner said of her Olympics selection. "It has been a really long four years. It wasn't my night last night. I am happy my federation was able to see beyond one bad skate."
U.S. figure skating chief Pat St. Peter defended the decision to name Wagner to the team over Nagasu.
"We have selection guidelines that have been put in place," said St. Peter, insisting that Wagner's strong overall season had tipped her over the edge. "If you look at Ashley Wagner's record and performance she has the top credentials. It is an objective analysis."