Vonn will compete in the three-race series at Lake Louise, Canada, starting Friday, but opted to skip Thursday's training runs to give her right knee one more day of rest.
Vonn, the four-time Audi FIS Alpine World Cup overall women's champion, had been sidelined for more than two weeks after a fall during a training run that re-injured the knee ligament she had surgically repaired last winter. She has opted to wait until after the Winter Olympics in February before undergoing additional surgery.
Her Wednesday training run at Lake Louise went well, and Vonn was cleared to compete in the grueling weekend series, which includes back-to-back downhills and a super G race Sunday.
"You know if your body is ready or not and I know that mine is ready," Vonn said, adding: "My goal yesterday was to ski solid and to ski my race line and I did that. I knew that if I could accomplish all those things in one run, then I don't need a second run (on Thursday)."
The U.S. Ski Association said in a written statement Vonn has won 14 times at Lake Louise, more than any skier in World Cup history.