The city has closed the beach at Hanauma Bay Nature Preserve due to high surf conditions.
The viewing area and exhibits will remain open to the public.
A high surf warning is in effect for all north and east shores for most of the Hawaiian Islands and west shores of the Big Island until 6 p.m. Thursday.
The National Weather Service said a north, northeast swell is generating 20 to 25-foot waves on the north shores and 10 to 15 feet on the east shores.
Lifeguards at Hanauma Bay will reassess surf conditions tomorrow.