Thousands of people filled North Shore beaches on Sunday, many watching surf contests and checking out the huge swell that formed overnight.

“Sunset Beach is firing its 8-to-10-foot local style, with about 12-to-15-foot faces, it’s a great way to kick off the vans world cup of surfing,” said Marty Thomas, World Surf League Hawaii, Tahiti Nui tour manager.

The swell only growing larger.

“It’s supposed to get bigger tonight and into tomorrow about 25-foot Hawaiian so it’s supposed to be about 35 to 40-foot faces,” Thomas said.

“It’s going to be washing out here at Sunset so more than likely we’ll be off here [for the contest] at Sunset but they’ll be on at Jaws on Maui,” he said.

Two time Peahi Challenge winner Billy Kemper competed at Sunset Beach on Sunday, he’s then flying to Maui to take on Jaws.

“Maui’s known for wind, it’s where I grew up, and I’m not scared of wind and people are going to have to adapt to the situation and overcome the opportunity. I’m ready, it’s going to be really big and really real,” Kemper said.

Sunday’s big swell bringing surprising relief to nearby homeowners.

It was just two months ago that homes along Ehukai Beach were severely threatened by sand erosion. Homeowners saying they’re extremely grateful for Sunday and Monday’s NW swell direction.

“When we saw the report and saw this coming we all took a sigh of relief I would say,” said one homeowner. Adding the swell is more West and will help bring some sand back.

Meanwhile, lifeguards at Waimea Bay were warning beach goers.

Lifeguards urging people to not swim, even warning the experienced swimmers.

“If you do not have fins, please do not go in the ocean. We are serious. Even if you have experience, these waves are unpredictable,” one lifeguard said over the megaphone.

One person needing assistance from the water. Ocean safety putting out caution tape and warning signs ahead of tomorrow’s massive swell.

“We’re anticipating this to be a large, life threatening swell,” Lt. Kerry Atwood, North Shore Ocean Safety said.

“We want everyone to understand it’s a no swim day, there’s no recreational swimming on the North Shore at all,” he said.

Ocean Safety is also urging people to stay off wet rocks and wet sand; listen to lifeguards and ask them questions.