Humphries, a back-to-back Olympic champion with former teammate Heather Moyse, piloted her sled to a two-run time of one minute, 55.73 seconds.
That was 0.35 of a second slower than Elana Meyers Taylor and Cherrelle Garrett of the U.S., who won for the third time in three races this season.
Belgium’s Elfje Willemsen and Annelies Holthof took the silver medal, 0.11 of a second back of the Americans.
Humphries, from Calgary, and Meyers Taylor made history earlier this season by becoming the first women to compete in a World Cup four-man bobsleigh event. They’re both piloting sleds with three male teammates this season.
Humphries won a silver medal in the two-woman event with Kate O’Brien at the World Cup stop in Calgary in December. She finished fifth with Lotholz in the season opener at Lake Placid.
In December, Humphries won the Lou Marsh Award as Canada's athlete of the year for 2014, during which she successfully defended her Olympic title in Sochi, Russia.