Weather for Hawaii: A Primer

Wondering what to pack? Here are the basics on weather for Hawaii. By: Marty Wentzel
Hawaii does get rain, with the leeward sides (south and west) getting less rainfall than the windward regions. // © 2012 Hawaii Tourism Authority/Tor...
Hawaii does get rain, with the leeward sides (south and west) getting less rainfall than the windward regions. // © 2012 Hawaii Tourism Authority/Tor Johnson

The Details

National Weather Service - Pacific Region
www.prh.noaa.gov

Tell mainland residents that you’re traveling to the 50th state and you’ll likely get groans of envy in response. Usually they’re thinking about the wonderful weather for Hawaii and wishing that they could crawl into your suitcase.

Without a doubt, Hawaii lays claim to one of the most ideal climates in the world, and that statement is true any month of the year. That said, when packing for your tropical vacation it’s helpful to know a few specifics about atmospheric conditions around the islands.

Here, then, is a primer on Hawaii weather. While there are exceptions to the rules, the bottom line is that Hawaii is basically a climatic paradise. Pack the sunscreen and bathing suit and bring along a hat to protect you from the sun. Then tell your mainland friends to get out of your suitcase and book their own vacations.

Seasons
Forget four seasons. In Hawaii you basically get winter, stretching from November through April; and summer, which runs from May through October. Unlike other destinations, however, there’s not much difference between the two seasons except that it rains a bit more in the winter than in the summer. Due to its relative proximity to the equator, Hawaii’s daylight length doesn’t vary much throughout the year, with 11 hours in the winter versus 13.5 hours come summer. Residents can easily forget what month it is, because the environment provides few if any clues.

Temperatures
How hot or cold it is depends on where you are in Hawaii. At sea level, the temperatures stay fairly steady throughout the year, ranging from an average of 78 Fahrenheit in the winter to 85 Fahrenheit in the summer, with nighttime temperatures about ten degrees cooler. But head to the higher elevations — Hawaii Volcanoes National Park or Haleakala Crater, for instance — and the mercury falls. That’s when you’ll be happy you packed that sweatshirt. Even during the warmest months, the state’s signature trade winds provide a cooling effect.

Rainfall
Again, the amount of rainfall depends on where you happen to find yourself. On the Big Island, the eastern town of Hilo gets more than 130 inches of rain annually. Compare that to the town of Kekaha on Kauai’s west side, getting just 20 inches; and Waikiki on Oahu’s south shore, with less than 25 inches. In brief, the leeward sides (south and west) of each island are generally drier while the windward regions (north and east) are wetter. Now you know why most of the state’s major resorts are located leeward.

Ocean Conditions
Throughout the year, storms that take place in distant oceans create different types of waves in Hawaii. North shore beaches are generally calm in the summer but experience huge swells in the winter, while the reverse is true at beaches to the south. Trust the lifeguards; if they post ocean warning signs, spread out your towel and stay on shore. When you do get into the water, you’ll benefit from the sun’s warmth, which keeps ocean temperatures pleasant even in the winter.

>