A High Surf Warning has been issued for most north and west-facing shores for what's expected to be a long-duration swell that could wash waves over some roadways along the affected coastlines.
The National Weather Service said the warning is in effect until 6 p.m. Wednesday for the north and west shores of Niihau and Kauai, and the north shores of Oahu, Molokai and Maui.
A High Surf Advisory is also in effect for the west shores of Oahu, Molokai and the Big Island.
Surf along north shores is expected to rise to 20 to 25 feet later Tuesday into Wednesday. West shores of Oahu and Molokai will rise to 13 to 18 feet, with waves of 8 to 11 feet for the west shores of the Big Island.
The high waves will mean that ocean water may occasionally sweep across portions of beaches, and roadways during period of high tide. The large breaking waves and strong rip currents will make it very hazardous to enter the water, and anyone who does so could face significant injury or death.
Breaking waves may also affect harbors, making it dangerous to navigate harbor entrances.