A Small Craft Advisory is in effect for Kaua'i, O'ahu, Maui County and the Big Island, according to the National Weather Service.

The windward coast of all the islands are affected. In addition, Kaua'i's northwest and leeward coast along with Big Island's leeward and southeast waters are under the advisory.

Channels between the islands and Maalaea Bay are also affected. The channels are Kaua'i, Kaiwi, Pailolo and Alenuihaha.

The advisory is expected to last until early Saturday, the weather service said.

A strong high pressure far northeast of the islands is responsible for the strong trade winds. Added to that easterly winds south of the high is generating high winds and seas, the weather service said. And with a moderate northwest swell building today, many marine areas will have seas of 10 feet or greater.