Dangerously high surf continued to pound the north and west shores of Oahu today, prompting warnings and resulting in dozens of ocean rescues.

The National Weather Service’s high surf warning for the north- and west-facing shores of isles from Kauai to Molokai, and north shores of Maui, has been in place since noon Tuesday, and remains in effect through 6 p.m. Thursday.

A large northwest swell that arrived Tuesday boosted surf to as high as 35 to 45 feet for Kauai County, and 30 to 40 feet for Oahu, Molokai and Maui.

By this afternoon, forecasters downgraded the surf heights to 20 to 30 feet for the north-facing shores, and 15 to 20 feet for the west-facing shores of those isles.

The high surf kept Honolulu Ocean Safety busy on both the north and west sides of Oahu, and lifeguards stayed past 5:30 p.m., when they are usually off, in those areas.

On Oahu’s North Shore, lifeguards rescued 15 individuals today, mostly from Waimea Bay, and took 1,440 preventative actions. On the West side, lifeguards rescued 32, mostly at Makaha Beach, and took 2,415 preventative actions.

Among those rescued was a man in his 40s who nearly drowned at Nanakuli just after 2 p.m. today.

Lifeguards were able to bring him to shore and administer aid until Honolulu Emergency Medical Services arrived and took over. EMS transported him to the hospital in serious condition.

On Tuesday lifeguards made 19 rescues on Oahu’s North Shore as surf picked up in the late afternoon, along with 350 preventative actions or warnings.

Forecasters say the swell is expected to lowly trend down through Friday.

A high surf advisory also went effect for the west-facing shores of Hawaii island at 6 a.m. today, and remains in place through 6 p.m. Thursday as well.

Civil Defense warned of large, breaking waves of more than 8 feet along the shoreline in North and South Kona, South Kohala and Kaui districts. Beaches in the area may be closed without notice.

For high surf warning areas from Kauai to Maui, ocean water can surge and sweep across beaches, impacting coastal properties and infrastructure.

The public should be aware of large, breaking surf, significant shorebreak and dangerous currents.

“Anyone entering the water could face significant injury or death,” officials said.

The weather forecast, meanwhile, includes mostly sunny skies on Thursday and a return of light to moderate trades traveling from east to west, with an increase of showers expected over Maui County and Hawaii island.

They are expected to pick up even more on Friday, and breezy conditions are expected across the state.

A small craft advisory has also been issued for most Hawaiian waters, from northwest of Kauai to the windward side of Hawaii island, through 6 p.m. Thursday.