An early season south swell is on the way and could push surf along O'ahu's south-facing shore from 4 to 6 feet this morning and 7 to 10 feet by this afternoon, the National Weather Service said.

A high-surf advisory has been posted for south-facing shores on all islands.

Elsewhere today, the surf is expected to be 2 to 4 feet along north-facing shores, 4 to 6 feet along east facing shores and and 3 to 5 feet this morning along west-facing shores, which could see sets of 5 to 8 feet by this afternoon, forecasters said..

The south swell that is approaching the state will hold surf above the advisory level of 8 feet along south-facing shores through Saturday morning, then begin decreasing Sunday through Tuesday. A small north northwest swell arriving today will build into the weekend.

Another shorter-period, small to moderate north-northwest swell will build Sunday then decrease into early next week.