The Hawaiian Islands are kept cool by NNE trade winds. Those are the winds that one experiences most of the time here. Occasionally those winds are replaced by Kona winds. These winds blow from the south and the weather becomes hot & muggy. For a couple of days over Christmas, Kona winds were blowing over Maui. With them the south shore became wetter than the north, it is normally the other way round, and the ocean on the north shore was pretty much calm - usually during the winter the surf returns to the north shore.
Last night the mugginess was broken by a torrential downpour on the north shore. It was welcome. Today, weak trade winds are blowing.