She posted a time of 101.32 to pip reigning C1 world champion, Mallory Franklin.

Fox has been undefeated this World Cup season and if she takes the world championship title she will become the first slalom athlete to go undefeated during an entire international season.

The dual Olympian had won the C1 world title for three years in a row before losing to Franklin last year.

"I think last year was really disappointing and frustrating but it happens sometimes so it's about learning and coming back stronger," Fox told ICF.

"This year I've had a great season and I'm just looking forward to racing," she said.

Fox also had the quickest time in the Women's K1.

'It's a good start and I'm feeling good on the water. Hopefully, I can keep that going on the weekend," she said.

Younger sister Noemie also qualified for the semi-final despite picking up two gate touches.

Jess will be back on the water Saturday morning AEST for the semi-finals of the Women's K1.