Hawaii Weather

Hawaii Weather:

What To Expect On Your Vacation To Kauai

Hawaii weather is a ‘hot’ topic for discussion when vacation planning. Travelers always believe their one-vacation-in-years is going to be in poor weather. Don’t read too deeply into local reports! Quite often seven-day reports are not an accurate representation of the actual weather. Take the time to understand the factors involved with our local weather. This will save you the anxiety of constantly checking the reports leading up to your BIG vacation. Learning the factors involved in local weather conditions provides an educated perspective on real island conditions. Surely you have heard the old adage “If you don’t like the weather, wait a minute and it will change”. This statement literally describes trade wind weather!



How Geography Effect The Weather


The Hawaiian Islands are located at 22 degrees northern latitude, which places our island home directly in the middle of the sub-tropical latitudes. Sub-tropical latitudes are generally cooler with less humidity than that of tropical latitudes located closer to the equator. The Hawaiian Islands are situated directly in the center of the strongest ‘trade wind’ belt in the world. Prevailing trade winds consistently deliver 5-15 mph winds between the north and east shores about 85% of the year. These trade winds help to moderate temperature and provide the perfect comfortable conditions.


Trade winds also bring passing showers. Showers are unpredictable and show up in random windward areas of the islands daily. Unlike the mainland, trade wind showers can be seen arriving and dissipating within minutes or hours, not days. These unpredictable showers are influenced by geographic and localized micro-climates. A “50% chance of showers” is a common daily report. As an active guide, reading Hawaii weather reports hourly for over a decade, the one truth about Hawaii weather is ‘what you see is what you get’. The most beautiful day of your entire vacation may have a weather report of 100% chance of heavy rain with a flash flood warning (always take warnings seriously when hiking or kayaking into the interior).


What To Expect When Traveling To Kauai


Yes, like anywhere, there is a possibility of some heavy days of rain. Most days of the year the weather is gorgeous somewhere on Kauai. Unless you are a long-term resident of the islands, in general, the seasons are barely noticeable. Climatically (average of temperature over a long period of time), Hawaii only shows an 8 F degree temperature change throughout the year. Rarely do beach side temperatures get below 65 F degrees in the middle of winter and above the 85 F degrees on the hottest summer day. Although this unique trade wind weather and physical geography do allow for various micro climates around the island, the northern and eastern shores are typically the most comfortable weather due to the direct exposure to the trade winds. They also receive more moisture embedded in the trades, and this moisture generally comes through quick 5-minute rains with a return to sunshine.


The Edge Of Kauai Wind and Wave Illustration

The south and west sides of the islands are typically warmer and dryer being in the lee of the mountains. As the winds come on shore from the north and east, it must pass over the interior mountains. A process of orographic lifting (mountains cool air, then air changes from gas to liquid state) drains the air of its moisture. Lets break it down by looking at the root of this word. Oro is Greek word for ‘mountain’ and graphic implies ‘physical geography’. The air being pushed off the ocean into the mountains is forced to rise by the shape of the mountains. As moisture trapped in air ascends over the mountains it cools, condenses and turns into a liquid state. When that same air mass descends over the backside of the mountains it is has already lost most of its moisture in the form of interior rains, leaving a warmer, dry air mass as it continues towards the islands leeward shores.

Another interesting fact is that Mt Waialeale, located in the center of Kauai, receives more rain than anywhere else on earth (430 inches on average). This process of releasing moisture from the air into the mountains provides dryer air to the opposing south and west sides of the island. The interior, and the north and east shores are typically cooler, moister and have lush jungle-like landscapes. The south and west shores are typically drier, with more desert-like landscapes. When traveling into the mountains of Hawaii, everything you just learned changes. For every 1000 feet gained in elevation, expect the temperature to drop 3-5 F degrees. It’s always good to bring at least one change of warm clothes.


When is the best time of year to come?


People always ask us “When is the best time of year to visit Kauai’?” The short answer is “always”. Spring and summer (April-Sept) generally offer drier weather. Fall and winter generally are less crowded (except for school holidays). There is something great about Kauai anytime of the year. Don’t let the weather forecast keep you from the vacation of a lifetime. The most important thing to remember is to use lots of sunblock and drink extra water. Although the climate is often very comfortable, Hawaii has much stronger UV rays than most places in the lower 48. Make sure to apply sunblock liberally and always! If you have any other questions about the local weather conditions, give us a call at 800-380-KAUAI(5282) today.


A few good Hawaii weather resources…

Hawaii Visitors and Convention Bureau (HVCB) Member