The Hawaiian Islands have a moderate tropical climate with gentle northeasterly tradewinds and warm Pacific waters almost year-round. Temperatures vary little from place to place, except at higher elevations.

The average annual temperature of 75 degrees Fahrenheit (23.9 degrees Celsius) fluctuates only a few degrees from summer (May through October) to winter (November through April). The recorded temperature in the state has ranged from 12 degrees F (-11.1 degrees C) near the summit of Mauna Kea in 1979 to 100 degrees F (37.8 degrees C) at Pahala (on the Big Island of Hawai'i) in 1931. Unlike the temperature, Hawai'i's rainfall varies tremendously according to location. The highest amount of rainfall is usually at moderate elevations on the windward (east) sides of the islands and is due to moisture-laden oceanic tradewinds. Leeward (western) locations are drier, because they are shielded from the damp winds by mountains.