LOS ANGELES — Massive waves are aiming for California, and some of the world's best surfers are waxing up their boards.

In Half Moon Bay, organizers with the World Surf League are preparing the Mavericks Challenge, a contest that happens only when the surf is "huge." The event was a no-go last year.

"We are closely monitoring the conditions to potentially run on Tuesday or Thursday next week," Mike Parsons, the league's Big Wave Tour commissioner, said in a statement.

Ken Collins, from left, and Tyler Fox surf a giant wave during the second heat of the Mavericks surfing contest in Half Moon Bay, Calif on Feb. 12, 2016. Ben Margot / AP file

For the first time since 1999, when it was known as the Titans of Mavericks, women will compete in the contest. Ten women are scheduled to surf against each other.

The swell was expected to strike the Bay Area, including Mavericks southwest of San Francisco, on Sunday and Monday and remain strong for a few days, forecasters with the National Weather Service said.

The National Weather Service in San Francisco issued a high surf warning for Sunday and Monday, adding that waves at "favored locations" could reach 50 feet.

Surfline.com lead forecaster Kevin Wallis said the faces of waves at Mavericks could reach 60 feet on Monday.

Wallis was in Hawaii for WSL's Pipe Masters contest on Oahu's North Shore. He said the swell would hit the surf spot known as Pipeline, but that it could be so large it could shut down the contest Sunday.

He said the same could be true for Mavericks, which may be why organizers are waiting until Tuesday or later to hold the event.

"It's a question of surfer safety," Wallis said.

Jeff Clark, who's credited with being the first surfer to ride the waves at Mavericks, said the south winds and rain expected Sunday could ruin the wave. He said he's been informally advising the WSL.

"We hope the ocean cleans up enough to approach it Monday," he said.

Clark's shop in Half Moon Bay, Mavericks Surf Company, is where first responders share their worst-case contest plans and global wave chasers check in for the latest reports.

"Everybody’s coming in to see what Maverick's will produce in this coming week," Clark said.

The legendary big wave surfer said he plans to be on water rescue duty during the contest and that he might use a jet ski to get towed into a few waves beforehand.

"It's going to be big," he said.

Lifeguards will be on high alert. Some of the ablest bodies in the world of surfing have died competing at Mavericks, including boldface names Mark Foo in 1994 and Sion Milosky in 2011.

James Behrens, co-manager of the Coastal Data Information Program at Scripps Institution of Oceanography in La Jolla, said a big low-pressure system between Alaska and Hawaii has been churning up the water.

The west-northwest swell generated off Alaska's Aleutian Islands will send waves up and down the West Coast, forecasters said.

"It’s going to send swell anywhere that’s got northwest exposure in the Pacific," Wallis said.

The swell was expected to lose energy as it moved down the coast, but some spots in Southern California could get waves of up to 12 feet.

"Unless you’re an experienced surfer or swimmer, do not go in in the water at all," said NWS marine forecaster Stefanie Sullivan.