A large west-northwest swell will build across the state on Monday, bringing warning-level surf to some of the islands, the National Weather Service said.
A High Surf Warning is in effect for north- and west-facing shores of Niihau, Kauai, Oahu, Molokai, and for north-facing shores of Maui. A High Surf Advisory has also been issued for west shores of the Big Island.
Both the warning and advisory are in effect until 6 p.m. Wednesday.
Ocean Safety officials on Kauai have also issued an alert, advising no swimming at all North Shore beaches, west of the Hanalei Pavilion to Ke'e Beach, including 'Anini Beach.
Forecasters said surf will build to 35 feet through the day. Surf is expected to peak Monday afternoon and evening, then will slowly subside on Wednesday.
Expect large breaking surf, shorebreak and dangerous currents. Water may also sweep across portions of beaches.