A high surf advisory is in effect for the north and west shores of Oahu, Kauai, Niihau and Molokai and the north shores of Maui, the National Weather Service said.
A northwest swell will build tonight and boost surf to a range of 16 to 22 feet along north shores tonight, the weather service said.
The west shores of Oahu, Kauai, Niihau and Molokai will see surf in the 10-to-14-foot range.
The weather service said the surf will be accompanied by a heavy shorebreak and strong currents, making swimming difficult and dangerous.
The advisory is set to expire at 6 a.m. Thursday, but could be extended.