After teaming up with Sylvia Hoffman to win at Koenigssee last week, Humphries combined with Lauren Gibbs to succeed again in Switzerland on Saturday.
The USA pairing won by 0.16 seconds from Mariama Jamanka and Kira Lipperheide who clinched second spot by one hundredth of a second as Germeny's Stephanie Schneider and Leonie Fiebig had to settle for third place.
It was Humphries' fourth World Cup victory of the season, extending her lead to 73 points at the top of the standings ahead of the final race at Sigulda, Latvia, on February 14.
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