A high surf warning has been issued for the north and west shores of isles from Niihau to Molokai, and north shores of Maui, due to a huge, northwest swell, effective until 6 a.m. Friday.

The National Weather Service expects “dangerously, large, breaking waves” of 25 to 35 feet along affected north shores as that swell rolls through the isles today through tonight.

Surf for west shores is expected to reach 20 to 25 feet.

Officials warn of ocean water occasionally sweeping across beaches, very strong, breaking waves, and strong currents. Anyone entering the water could face significant injury or death.

A more northerly, overlapping swell, meanwhile, brings a high surf advisory to the north shores of Hawaii island through 6 a.m. Friday. Surf there is expected to reach 12 to 16 feet.

Today’s skies are expected to be mostly cloudy, with more extensive cloud cover for the windward sides of Oahu, Molokai and Maui, and scattered showers.

Highs today range from 79 to 84 degrees Fahrenheit. Lows tonight dip to 64 to 69 degrees.

Moderate trades of 10 to 20 mph today slow down to the light and variable range tonight as another front approaches from the northwest.

While surf on north and west shores are pumping, surf for east and south shores remains stable, at 3 to 5 feet and 1 to 3 feet, respectively, today and Friday.

A small craft advisory remains in effect for waters northwest of Kauai to windward Hawaii island through 6 a.m. Friday as well.

Although surf on north and west shores will ease back to advisory levels on Friday, forecasters say more dangerous surf is on the way.

Forecasters expect another large, northwest swell to peak on Saturday, bringing warning-level surf for the north and west shores of smaller isles through the weekend.