Lifeguards rescued 13 people off Oahu as big surf pounded north- and west-facing shores.
The rescues included two men in their 20s who were about a mile off Mokuleia Beach Park, clinging to a body board.
Meanwhile, lifeguards completed about 2,800 preventive actions, keeping people from venturing into unsafe conditions.
Wave heights on the North Shore were set to peak Friday night, and were to hit 35 feet.
A High Surf Warning has been issued for north- and west-facing shores of Oahu, Niihau, Kauai and Molokai, and north-facing shores of Maui.
The warning truns through 6 p.m. Saturday.
A High Surf Advisory has also been posted for west-facing shores of Maui and north-facing shores of the Big Island.
Forecasters say a large, long period northwest swell started building Friday morning and will start declining on Saturday.
On Kauai, officials closed all North Shore beaches — from Hanalei Bay to Anini Beach — to swimming because of the conditions.
The monster waves could cause significant shorebreak and dangerous currents, the National Weather Service warns.
Copyright 2017 Hawaii News Now. All rights reserved.
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