A high surf advisory issued for the north shores of the isle chain from Kauai to Hawaii island remains in effect until 6 a.m. Wednesday.

A long-period north swell is expected to peak this morning, according to the National Weather Service, then gradually subside through Wednesday.

Surf is expected to reach 12 to 18 feet on the north shores of Kauai and Oahu, and 15 to 20 feet on the north shores of Molokai, Maui and Hawaii island.

In the forecast, meanwhile, showers and clouds are expected to linger over portions of the state through the middle of the week, affecting mostly windward areas.

While Kauai and Oahu may see some clearing by Wednesday, cloudy and damp weather is expected to continue on the windward sides of Maui and Hawaii island. Breezy trades will persist through Wednesday, while lighter winds are expected Thursday and Friday, which may allow afternoon showers to develop over leeward areas.

Vog from the eruption of Kilauea Volcano on Hawaii island could also reach smaller isles in the western half of the state later this week.