The Hawaiian Island's tropical weather is very consistent throughout the year with only moderate changes in temperature. And when you add to that mix Hawaii's moderate humidity, unchanging (and fragrant) northeasterly trade winds, and infrequent severe storms, well, conditions in Hawaii are most desirable.
There are only 2 seasons really: the summer months (called Kau in Hawaiian) that extend from May to October, and the winter months (Ho'oilo) from November to April.
The average daytime summer temperature at sea level is 85 degrees F. (29.4 C,) while the average daytime winter temperature is 78 degrees (25.6 C). Cooler conditions are common in the upper elevations and winter storms (though rare) do occur.
November through April bring the heaviest rains to Hawaii, however rainfall amounts vary each and every year due to moisture levels, individual island topography and many other variables.
The warm summer rains, though occasionally heavy, are usually brief and localized. Extremely heavy precipitation amounts fall in the upper reaches of the mountains on all of the islands.
For an interesting look at Hawaii precipitation amounts (by island) view this precipitation map.
Current Weather Conditions:
In these selected cities....
Seasonal Temperature Averages:
HIGH TEMPERATURES ( Fahrenheit/Celsius )
(Jan) 79/26 (Feb) 80/26 (Mar) 80/26 (Apr) 85/29
(May) 88/31 (Jun) 89/31 (Jul) 89/31 (Aug) 91/32
(Sep) 88/31 (Oct) 85/29 (Nov) 84/28 (Dec) 81/27
LOW TEMPERATURES ( Fahrenheit/Celsius )
(Jan) 67/19 (Feb) 68/19 (Mar) 65/18 (Apr) 73/22
(May) 75/23 (Jun) 77/24 (Jul) 77/25 (Aug) 77/25
(Sep) 75/23 (Oct) 73/22(Nov) 72/22 (Dec) 66/19