A large north-northwest swell continues to pump surf up to 15 feet along affected shores of all islands.

A high surf advisory was extended this morning through 6 a.m. Thursday. The north and west shores of Kauai County and Molokai, the north shores of Oahu and Maui and the east shores of Maui and Hawaii island are covered under the advisory.

Forecasters expect waves up to 10 to 15 feet along the north and west shores of Kauai County and Molokai and the north shores of Oahu and Maui. Maui’s east shores could see surf up to 8 feet, while the east shore of Hawaii island is looking at surf up to 6 to 9 feet.

“Beachgoers, swimmers and surfers should heed all advice given by ocean safety officials and exercise caution,” the National Weather Service said in an advisory.