Big Island Weather: When is the Best Time to Visit?

The Big Island of Hawaii is a gorgeous island and one with a lot of different types of terrain and environments. Some parts of the island, Hilo and Puna, will see significantly more rain than other parts of the island, but overall, the Big Island of Hawaii is best characterized by a warm and tropical climate all year round. With such lush beauty, there really isn’t a bad time to visit Hawaii, but there might be some months you might prefer booking your vacation in over others.

Because the weather can fluctuate depending upon where you are on the Big Island, we’re going to zoom in on Kailua-Kona’s annual temperatures as it is the most popular resort spot on the island. Kailua-Kona’s coastal weather patterns also best reflect other parts of the island where visitors are most likely to base their vacation. 

Month-by-Month Look at Weather to Expect on the Big Island

January
January is one of the coolest months of the year, with an average low of 68 degrees Fahrenheit and an average high of 81 degrees Fahrenheit. Rainfall during this month is about 2.41 inches.

February
February is the last month of winter for the Big Island, although it boats the same average lows (68 degrees Fahrenheit) and highs (81 degrees Fahrenheit) as January. Visitors during this month will, however, see less rainfall with only an average of 1.5″ of rainfall each February.

March
Officially the first month of spring, temperatures start to rise during March with an average low of 70 degrees Fahrenheit and an average high of 82 degrees Fahrenheit. Rain is still at a minimum with an average of 1.78″ of precipitation accumulated.

April
April holds onto the same average highs (82 degrees Fahrenheit) and lows (70 degrees Fahrenheit) as March, but with a bit less rain. Only about 1.36″ of precipitation is collected during April.

May
Temperatures climb just a touch in May, with an average low of still 70 degrees Fahrenheit, but an average high of 83 degrees Fahrenheit. May is the last month of spring, and it is a rainy spring month with an average of about 2″ of accumulated precipitation. 

June
Things start to really heat up in this first month of summer. The average high in June is 85 degrees Fahrenheit and the average low is 73 degrees Fahrenheit. The rain during this month dries up some, with just under 1″ of precipitation accumulated. During this month, the ocean temperature also increases to 78 degrees Fahrenheit, which is one temperature above the lowest range considered as very warm and comfortable for all swimmers. 

July
July offers peak summer weather for guests and residents of the Big Island. Here, the average is low is a very warm 74 degrees Fahrenheit and the average high 86 degrees Fahrenheit.  This is also the driest month of the year for the Big Island’s western coast, with just 0.7 inches of precipitation accumulated. 

August
August is the month in which summer temperatures start to wind down. The first couple of weeks is going to be the hottest of the year, with an average high of 87 degrees Fahrenheit for the month and an average low of 75 degrees Fahrenheit. You can also expect a bit more rain during this month, especially towards the end of August with an overall average of 1.39″ of precipitation. 

September
Temperatures start to cool down during Septe4mber but only just as the high during this month is 86 degrees Fahrenheit and the low 74 degrees Fahrenheit. Not quite as much rain, however with just .84″ of precipitation generally collected.  

October
October is a gorgeous autumn month for the Big Island. Here, water e temperatures are at what is quite arguably an ideal swimming temperature at a warm 79 degrees Fahrenheit. Outside, the air temperature here is an average high of 86 degrees Fahrenheit and an average low of a comfortable 74 degrees Fahrenheit. This month does, however, get more rain with an average of 1.34 inches of accumulated rainfall.

November
Considered by some as the last month of fall and by others the first of winter, November remains hot in Hawaii. The average high barely cools off at 84 de4grees Fahrenheit and the average low dips to 71 degrees Fahrenheit. Rainy days stay about the same as October with 1.28 inches of rainfall.

December
December is the busiest month for Hawaii, with many northerners opting to escape the snow and sleet back home and enjoy a warm holiday season on the Big Island — and it certainly is warm. December might be peak winter for the island, but others will find it resembles their peak summer with an average high of 82 degrees Fahrenheit and an average low of 69 degrees Fahrenheit. There are quite a few rainy days, however, with an accumulated rainfall of 2.8″, the most out of the year. 

When Should I Visit for the Best Time on the Big Island?

A lot of people choose winter to go to the Big Island and other Hawaiian islands during the winter to escape their own cold and blustery temperatures back home. December and January are often also easy months to visit with holiday vacations. However, while it is easy and the temperatures are warm and enjoyable, this generally isn’t the best time to go to Hawaii if you have a choice. The water temperatures are chillier, the resorts crowded and more expensive, and higher chances of rain.

If you want to go to Hawaii to enjoy lazy days swimming in tranquil waters, then summer is for you. June and July are both drier months with exceptionally warm weather both in and out of the water. However, this is the second busiest time for these very reasons.

If you want to enjoy a less crowded time on the Big Island but still get plenty of swimming in, then October is the ideal time for you. During October, water temperatures are still quite warm, and you will have plenty of days that are hot enough to swim but cool enough to enjoy hiking and other activities.