You may hear the words leeward and windward to describe areas of the island, but not know what that means. In a nutshell, they essential describe how much rain an area gets and how tropical or arid an area is.
The trade winds blow from the northeast of the Hawaiian islands to the southwest. (By the way, you’ll likely hear locals refer to the trade winds, simply as “the trades”) The trade winds bring moister air. As the trade winds hit a volcanic mountain, the air cools and creates clouds. Then the clouds produce rain on the windward side. The leeward side is the drier side or the side where the trade winds pass after they hit a mountain. The windward side is the wetter side. The way I try to remember it is this way – the winds hang out and produce rain on the windward side.
As a picture is worth a thousand words, let’s look at a visual description of leeward and windward. Let’s start with leeward.
Leeward Kohala Coast of the Big Island
Now contrast the relatively dry landscape of the leeward side with very little greenery to the lush windward side.
Windward Side of the Big Island (along the 4-mile Scenic Road)
I love both the leeward and windward parts of the islands. I love that in a short drive you can see such a drastic contrast.
In general, the north and/or east sides of each Hawaiian Island tend to have the windward climate. In contrast, the south and/or west sides of the islands are leeward. The following satellite map of Hawaii’s Big Island illustrates this climate trend. The greener sides are mostly on the east side of the island, while the drier sections are on the west side.
Now let’s look at a satellite image of all the Hawaiian Islands as a whole. The following image shows the greener windward sides concentrated towards the east and north of each island. The drier, leeward, areas are concentrated on the south and west sides.
Ah, doesn’t Hawaii rock?