Photo gallery: South shore swell

Big wave riders rejoice! Other beachgoers beware!

A winter storm from near New Zealand is bringing 8- to 12-foot surf today to south shores across the state, the National Weather Service forecast Monday.

"Everybody’s pretty excited — all the surfers," said Jim Howe, operations chief for the city Ocean Safety Division, but also shared some sobering words for all oceangoers.

"For visitors: It’s the same size surf as Hurricane Irene on the East Coast," he said. "This is big stuff and can be dangerous and harmful. It’s not a storm, but it’s the same size of surf as what Irene kicked up on the East Coast. It’s very hazardous for those who aren’t very experienced.

"For the surfing community: Watch out for each other. It’s going to be great; it’s going to be fun, but keep an eye out for each other."

The south swell was expected to increase Monday night and reach advisory levels, between 8 and 12 feet, through tonight and stay at advisory levels through Wednesday, diminishing Thursday night, said National Weather Service forecaster Henry Lau. West-facing shores will have surf between 6 and 10 feet, which is below advisory levels.

Surf was already pounding the south shore of Oahu Monday, with seven to eight feet at a spot called Browns at Diamond Head and at Castles — a bluewater wave outside off the reef’s edge — off Queen’s Surf in Waikiki.

The surf reached 12 feet Monday in a couple of sets at Ala Moana Bowls, Lau said.

A visitor suffered a cervical-spinal injury late Monday afternoon after being slammed head-over-heels in nearshore waters in Waikiki, which is not known for a shorebreak, Howe said. The visitor was taken by ambulance to an area hospital.

The disappearance of a diver a half-mile off Kahala may also have been related to the swell.

"A fairly large rip current is starting to develop," Howe said. "A lot of water is moving around."

This swell, originating 3,500 miles away, pushes a lot of water inside the reef, and strong rip currents go back out to sea, Howe said.

The surface was pretty murky, but down below at 90 feet deep, where the dive occurred, it would have been clear, he said.

The swell also caused a lot of sand to be kicked up, he said.