The National Weather Service issued a high surf warning for north shores of most islands until 6 p.m. Saturday.

Surf of 20 to 30 feet is expected for north shores of Niihau, Kauai, Oahu, Molokai, Maui and the Big Island.

Beachgoers can expect ocean water occasionally sweeping across beaches, strong breaking waves and strong currents.

“Waves may break onto some roadways and deposit rocks and other debris, especially around high tide late tonight,” forecasters said.

High surf closed Bayfront Highway in Hilo this afternoon, Hawaii County police reported.

The current swell is coming in from a more northerly direction than typical winter swells. Forecasters expect a new northwest swell to arrive Saturday, possibly bringing advisory-level surf to west-facing shores.