Indonesia is split by the equator so it has tropical climate with high temperature and humidity throughout the year. Monsoon also affects the climate of Indonesia, bringing raining season (December to March) and dry season (April to September).
Western Sumatra, Java, Bali, the interiors of Kalimantan, Sulawesi, and Irian Jaya are the most predictably damp regions of Indonesia in raining season.
September to December is the tropical typhoon season of this area, some of Indonesia islands could be attacked by typhoons during this period.
Then when is the best time to visit Vietnam?
You can visit Indonesia all year round. Indonesia is the largest Muslim country in the world and as such, Ramadan (July) is a big deal. The main Indonesian holiday period falls at the end of Ramadan and you can expect most resorts to be full of domestic tourists and a consequent price rise during this time. Therefore, travel peak seasons in Indonesia are end of Ramadan, Christmas and mid-June to mid-July, Java, Bali, Sumatra and Sulawesi are all crowded during this periods.
Sumatra and Java：The best time to travel to Sumatra and Java is between May and September. The rainy season on Sumatra and Java begins from November and lasts until March. The rains tend to come around the late afternoon, so you’ll still have pretty mornings in most cases. April and October are decent times to visit as well, but keep in mind that monsoons in these regions can be very heavy and make roads inaccessible. Temperature average is around 22-29 Celsius degree year round.
Sulawesi: it has two opposite climates – which isn’t much of a surprise when you take into consideration its funky shape and the fact that it’s on a geographical borderline. The South-West part of Sulawesi has a monsoon season that begins in October and typically lasts until March.
The North of Sulawesi, around Manado, sees most of its rain fall in June and July and has a dry season from August to October. Temperature is also vary significantly on this island – it can be extremely hot along the coast with temperature around 34 Celsius degree but the hills are rather cool with a maximum temperature around 24 Celsius degree.