Vonn, who won an Olympic downhill gold medal in February, finished in a time of 1 minute, 20.72 seconds and beat the field by almost a second for her first World Cup win of the year.
“I dropped the hammer a little bit more and believed in myself,” Vonn, who won in Lake Louise for the eighth time in six years, said in comments distributed by the U.S. Ski Team.
Germany’s Riesch was second in 1:21.55 while American Julia Mancuso was third in 1:21.61.
Vonn’s victory came before fellow Olympic gold medalist Ted Ligety won the men’s giant slalom in Beaver Creek, Colorado. The reigning World Cup giant slalom champion, Ligety won by eight- tenths of a second over Norway’s Kjetil Jansrud.
It was the first time since 2006 that two Americans won World Cup races on the same day.
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