The Sochi 2014 Olympic bronze medallist came out on top with 85 points, finishing ahead of the United States’ Devin Logan on 80.40 and New Zealand’s Janina Kuzma with 74.

In a final that was reduced to one run due to bad weather, Onozuka timed her start to coincide with a lull in the winds.

She pulled off her backward double cork, despite being off balance, and credited her improved accuracy on grabs and on switching into skiing backward.

"My performance was okay," Onozuka told Kyodo News after the second World Cup win of her career.

"The conditions were far from great so I did well under the circumstances.

"I've taken in all the things I've been working on and I could give out everything I could.  

"You're not going to win unless you can do things other competitors can't."

Onozuka, 27, is a former giant slalom skier who reverted to halfpipe when it became an Olympic sport for Sochi 2014. 

Her compatriot Saori Suzuki finished fourth in California with 64.40 points.

The men’s halfpipe finals have been postponed until tomorrow due to the inclement conditions.