A day after Ester Ledecka became the first athlete to win both snowboard and alpine World Cup events, Schmidhofer mastered the Alberta course, securing her fourth World Cup win and third at Lake Louise.
The Austrian finished in a time of one minute 49.92 seconds, 0.13 seconds ahead of defending overall women's champion Mikaela Shiffrin.
Shiffrin, though, extended her overall lead despite narrowly missing out on her second career downhill win at Lake Louise.
Highlights: Shiffrin downhill runner-up behind Schmidhofer at Lake Louise
The start to proceedings was delayed once more due to inclement conditions, this time by 30 minutes after racing was pushed back by an hour on Friday, but when it got going the 30-year-old Austrian – who finished fourth overall last year – proved too good for the rest of the field.
Italian Francesca Marsaglia secured her first ever World Cup podium as she finished third, 0.43 seconds behind Schmidhofer.