Weather in Indonesia

Bali has a distinct wet season from November to March (with January being the wettest month), and a dry season from April to October. The temperatures are consistent throughout the year, averaging 23°C to 33°C. It can feel much hotter in the wet season as humidity averages 80% or more. It's cooler at higher elevations like Mt Batur and along the coast where the sea breeze offers a reprieve from the heat. If you want to snorkel or dive, it’s best to go in the dry season as the monsoon can impact water visibility.

The monsoonal patterns in Sumatra differ as the equator splits the island. The north is more tropical with year-round rain, although October through January tend to be the wettest months. In contrast, the south has a more distinct wet season with heavy afternoon downpours from October to March. Year-round temperatures average 21°C to 32°C, but it's slightly cooler in the Minangkabau Highlands. Travelling around the national parks in the wet season can be trickier due to flooding, and you'll need to take extra precautions against mosquitoes and leeches.

Java is home to the Indonesian capital of Jakarta. It's hot and humid all year with average highs of 23°C to 33°C, but cooler temps prevail at higher elevations like Mt. Bromo. Java's rainy season is from November to April, with the western side of the island experiencing the wettest weather. The dry season (May to October) is the best time to hike up volcanoes or cycle through rice paddies.

The province of Nusa Tenggara (comprising Lombok, Gili, Flores and Sumba) typically has its dry season between April and September. These months offer ideal conditions to hike Mt Rinjani or dive/snorkel off the coast of Lombok, Komodo National Park or the Gili islands. The wet season is from October to April, with December and January seeing the most rainfall. The temperatures are similar to Bali, with averages of 20°C to 30°C.