Bali is located about eight degrees south of the equator and lies in the Indian Ocean. The climate is warm (26 to 28 degrees Celsius) and humid throughout the year with very little variation in average temperatures. Differences between day and night temperatures are about nine degrees and duration of the daylight hours remains uniform. There are two distinct seasons, simply known as the wet and the dry. There is some overlap during the transition months and some surprises during both seasons.
November to April is the rainy season and December to March are the months when it really pours (90 mm average). There can be sudden thunderstorms that reduce visibility and sometimes it rains continuously for days. Flooding can make roads unusable and several outdoor activities unavailable. Far fewer tourists arrive on the island during the wet season. Hotels are empty, beaches deserted and tourism businesses offer their rock bottom rates. This can be a great time for surfing since the waves are bigger (and you get wet anyway). It is also an excellent time for scuba diving. Most dive sites still have underwater visibility up to 30 meters and there is no wait for bookings.
May to October is the dry season when it does not rain (much) although humidity stays at about 85%. It is also the ‘summer’ since May is the hottest month (by two degrees). July and August are the peak tourism months when hotel rooms can cost three times and restaurants are almost never accessible without advance reservations. Most of the popular beaches are crowded and the tourism support infrastructure of the island is stressed to its limit. This makes the off-peak summer months of April, May, June and September rather attractive. The rooms are still affordable and there are plenty of outdoor activities to pick from.
An interesting geographical phenomenon is Bali’s volcanic mountains. Located in the north of the island, some peaks rise above 3,000 meters. The hills receive significantly more rainfall than the low-lying coastal areas and are also cooler. Surrounded by protected forest reserves and located near scenic rivers, many of Bali’s northern regions make for excellent year-round vacation spots, especially for eco-tourists.
Peak & Off Peak Seasons
Peak and off peak seasons may also affect your decision on when to travel to Bali as the most popular times are not only the busiest but also more expensive. July and August are usually the busiest periods of the peak season with many families holidaying during school holidays and the same can be said for the Christmas/New Year period. Off peak seasons are cheaper in an attempt to attract more visitors and some of the best deals can be had between March and October.