When To Go

When you take your trip may be dictated by when you can take time off work or when children are out of school.  But, the more flexibility you have in the time of year you take your trip, the better the chance to reduce the cost, minimize crowds of other tourists, and determine the chance of clouds and rain during your trip.

High Season Versus Low Season
You will want to consider the travel seasons during trip planning if you are concerned about cost and crowds.   Hawaii's high season is from mid-December through mid-April.  From December 15th until mid-January is the busiest tourist season.  If you are planning a trip during that time make reservations early, expect to pay high prices for everything, and get ready for crowds.  Mid-June through August is also a high season.   School is out and many people vacation during summer months.  Bargains are harder to find and you will find plenty of company with families on vacation.  The low seasons, or off seasons, are spring (mid-April through mid-June) and fall (September through mid-December).  Prices will be much lower than during high season and great deals can often be found on vacation packages.

Island Climate
Average temperatures normally vary no more than 15° F from one part of the year to another.  You will sometimes hear the term microclimate used because temperature and rainfall can vary greatly from one part of an island to another spot on the same island.  For example, Mt. Waialeale on Kauai receives an average of 440 inches of rain per year (more rain on average than any other spot on earth) but Waimea Canyon, just a few miles away, is almost a desert.  Hilo on the Big Island is the wettest city in the U.S. but only 60 miles away, it rains less than six inches a year.  If you don't like the weather in one area you can often just go to a different part of the island. 

Temperatures
Hawaii doesn't really have distinct seasons.  There is  winter which is warm, and summer which is warmer.  Temperatures are hottest from July through September when daytime highs will be at or near 90°F (30°C).   Even in "winter" the daytime temperature is usually in the 80's F.  The coldest months are February and March with nighttime lows near 60°F (18°C).  Temperatures drop with altitude and there is frost above 4,000 feet in the winter.  Of course, the top of the volcano's often have snow in the winter months.  However, a short drive will take you back to the beach where you can swim and sunbathe to thaw out.  The  average humidity ranges between 56-72 percent.  

Rainfall
It rains somewhere in Hawaii almost every day of the year.  Kauai and the Big Island's northern areas get more annual rainfall than the rest of Hawaii.  The surprise of island weather is that yearly rainfall may be more than 100 inches in one place and less than 20 inches just a few miles away.  Trade winds hit the east side of the islands first causing clouds to accumulate along mountain peaks and drop precipitation.  This is the windward side of each island and it is wetter and a little cooler. The western side of all islands is the leeward side and they are warmer and drier.  Most of the popular tourist resorts are on the warmer and dry leeward side of the islands; Honolulu on Oahu, Wailea, Kehei,  and Kaanapali on Maui, Kona and the Kohala coast on the Big Island, and Poipu on Kauai.  If you prefer it cool with a little rain or showers, try the windward areas; Hana on Maui, Princeville on Kauai, or Hilo on the Big Island.  

Much of the rain falls at night, on the windward side of the islands, and inland around the mountain peaks.  The odds are high that rain will not ruin your vacation.  In spring and summer showers are few.  Summer is Hawaii's dry season and most parts of the state where tourists stay receive virtually no rain then.  Sometimes August can be hot and humid but otherwise summer months are usually dry and gorgeous.  Rain is heaviest from November through March but, even then it is usually brief showers and won't spoil a vacation.   Remember, that if it's raining where you are, you can often find sunshine with just a short drive unless a large weather front is over the islands.  In that case, you may get away from the rain but you will still be unable to find sun.

Trade Winds
We delight in the trade winds which are named after the breezes that brought merchant ships to the islands.   They are lightest during the winter.  They usually blow from the northeast averaging about 12 m.p.h. and help keep you cool even when temperatures are near 90º F.  Sometimes trade winds break down and Kona (not related to the Big Island) winds blow from the southwest.  In summer and early fall Kona winds are synonymous with sticky weather.  In winter they can bring storms, but also some of the islands' clearest days.

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