Surf up to 18 feet is expected to roll into the north-facing shores of most islands Friday, prompting forecasters at the National Weather Service to issue a high surf advisory effective noon Friday through 6 a.m. Sunday.

The north- and west-facing shores of Niihau, Kauai, Oahu, Molokai; the north shore of Maui and the west shore of Hawaii island are covered under the advisory. Weather officials expect wave heights of 14 to 18 feet along north-facing shores and 8 to 12 feet along most west-facing shores. The west shore of Hawaii island can expect wave heights of 5 to 8 feet.

Weather officials warn beachgoers to heed all advice given by ocean safety officials.