Daytime high temperatures on Maui range from about 78 degrees in the wintertime to about 87 degrees in the summertime. This slight variation in temperature during the year is due to Hawaii's proximity to the equator and the cooling effect of the surrounding ocean during the summer.
Because the weather on the islands is usually very mild and pleasant, there is really no bad time to visit. The weather can be rainy and wet from the last few months of the year until March, but the rain is not drastic enough for any vacationers to avoid the island during particular months. Also, if it does rain, it can do so in specific locations and also be over quickly.
The water that surrounds the Hawaiian Islands, including Maui, is warm all year. In the winter, water temperature averages 75° and in the summer 82°. Surfing, which is one of the most popular sports on Maui, can be practiced all year long but the waves are bigger on the north shores during the winter months and south shores during the summer months.
Whale season starts in December and generally is over by the end of April. February is the peak of the season which provides visitors with the ability to see tons of whales in the ocean from various tour operators. You can even see them breach out of the water from viewpoints on the highway.
Maui Weather shows Lahaina's monthly average high, low and ocean water temperatures. Historic rainfall and temperature charts are also available for many Maui towns.
Beyond the weather, another deciding factor on when to go is what time in the tourism calender your vacation is. Maui has a pretty consistent ebb and flow as far as how many tourist are on the island at a particular time. The busiest times are when school students have vacation. This allows families to come to the island together and many take advantage. Times like summer vacations, spring break, Thanksgiving and Christmas are the most effected. On the other hand, the times right before or after these dates are always quiet. This makes getting reservations for activities and accomodations easier.
Mosquitos are common on the Hana side in late August, especially in lawn areas. Just be sure to keep doors closed. Generally speaking mosquito repellent is not needed, with mosquitoes only being a problem at night.
