A high surf warning is in effect for most islands until 6 p.m. Sunday as a high pressure system building north of the state prepared to bring strong wind gusts to the islands.

Forecasters at the National Weather Service have issued a warning in anticipation of surf reaching heights of 20 to 25 feet by Saturday night on Oahu’s North Shore and along the north- and west-facing shores of Niihau and Kauai.

Surf along the west shores of Oahu and Molokai is expected to build to the 15-to-20-foot range Saturday night before diminishing during the day Sunday.

The warning also includes the north and west shores of Kauai, the north-facing shore of Maui and the west shore of the Big Island.