The National Weather Service issued a high surf warning for north and west shores of Oahu, Kauai and Niihau.

Wave heights are predicted to increase overnight and Monday to 20 to 30 feet along the north and west facing shores of Kauai. Oahu’s North Shore should see surf of 20  to 25 feet and west shores should get 15 to 20 foot surf, forecasters said.

The high-surf warning is extended to Molokai and Lanai beginning at 6 p.m. Monday. Surf on north facing beaches is expected to be 20 to 25 feet and west shores should also see 15 to 20 foot wave faces.

A high-surf warning indicates that dangerous, battering waves will pound the shoreline, resulting in dangerous swimming conditions and rip currents.