A high surf warning remains in effect today but the large North Shore swell is expected to start diminishing tonight.

The National Weather Service’s warning covers north and west shores Niihau and Kauai and north shores of Oahu, Molokai and Maui.

A high surf advisory is in effect for east shores of Kauai, Molokai and Maui; west and east shores of Oahu; and north and east shores of the Big Island. The warning and advisory are in effect through 4 p.m. today.

Forecasters said the large north-northwest swell will bring waves of up to 25 feet to the north shores of Kauai, Oahu, Molokai and Maui. Eastern shores will see waves with faces of up to 10 feet, they said.

The high surf will make for dangerous swimming conditions and deadly rip currents, said authorities, who say beachgoers should exercise caution when in or near the water.