When the driver of the rental car shuttle at Kona airport gives his little “welcome to the Big Island” speech, he will undoubtedly tell you that Hawaii Island is like a microcosm of the planet, with 10 of the world’s 14 or 15 identified climatic zones.
Those of us who live here can attest that it is also an island of microclimates, as the mountainous topography and variety of winds sometimes create little pockets where the weather differs significantly from locations a few miles on either side. “How much rain does it get here?” is one of the questions Big Island real estate agents hear most often.
Hilo on the Big Island’s East side is the wettest city in the United States, receiving at least 100 inches of rainfall in even its driest years. The Kohala Coast gets only a tenth of that rainfall, which is why the resorts are located there in the abundant sunshine (the eternal green of the golf courses, the palm trees and tropical flowers are the result of ample irrigation). Kona coffee depends on afternoon rains that are typical of the summer months, whereas the green of the Hawi to Pololu area in North Kohala is thanks to spring rains carried on the prevailing trade winds.
Under the shelter of Mauna Kea, upcountry Waimea (Kamuela) is split into a dry side and a green side. Due to its elevation, Waimea residents can be identified by the fact that they own lots of hoodies and indulge in leather jackets in the winter and some homes even have forced air heating.
Big Island Rainfall Map
I mention that areas have different seasonal patterns, because seasonal weather is especially important in deciding which district of the Big Island is right for you when you are looking at buying property here for part-year use, or for agricultural uses. And just using the averages does not really convey what it is like living in a given location. For example, Seattle has a reputation for having a rainy climate, but its annual rainfall of 36 or 37 inches is less than in many places without the reputation such as agricultural Sonoma, California. The difference is in the number of days the weather is damp. The psychological experience is very different when you have clouds and rain almost every day, versus a pattern of sunny days and evening squalls, or a couple of wet winter months followed by beautiful summers.
The compact size of the Big Island also is an advantage when it comes to weather. Visitors staying in the dry Kohala Coast resorts are often astonished when they turn the corner into Hawi and see green pastures and lush tropical valleys with waterfalls reminiscent of Kauai. Conversely, when those of us living in Hawi or Kapaau, or Waimea tire of winter rain, all we have to do is drive 20 minutes to bask on a sunny beach!