The eastern islands such as Sulawesi and the Moluccas, are getting back to their peak weather conditions whilst the central and western islands, such as Bali, Lombok and Java, are just hanging on in October. Get lucky and the first few weeks can be perfect due to the significantly reduced visitor numbers. If you intend to climb one of Indonesia's many volcanoes, such as Mt Bromo or Mt Rinjani, then don't leave it later than October as rainy season will soon make climbing conditions too dangerous.
NB: the westernmost point of Indonesia is a full 3200 miles from the eastern most tip, so it should come as no surprise that summarising the weather is not straightforward. The tables above split the ‘country’ (made up of 17,508 islands) into two regions - the western & central islands and the eastern islands (that sit to the east of the Wallace Line), however we encourage you to read the more detailed summaries below as there can be significant variations in conditions between the islands within each group.
October is another hot, dry month across the island of Java, in much the same vein as September. Temperatures typically range from a very warm 24°C at night to highs of 33°C during the day. If you are planning on climbing Mt Bromo or Mt Ijen, this is the last month of the year to do so (before the rains arrive).
October is still a good time of year to visit Bali. Rain should be expected although only an average of 8 days over the month and rainfall comes in the form of short, tropical downpours. Temperatures remain warm (avg temp: 27 °C).
It's still possible to dive around Menjangan & West Bali National Park as these areas are among the most protected dive spots on the island, although conditions aren't as favourable as previous months.
Lombok & the Gili Islands, Flores & Sumba are still enjoying predominantly dry, sunny days throughout October, however as the month rolls on, those odd afternoon downpours begin to get heavier and more persistent. Temperatures start to rise with an average of 28°C, although humidity levels are at their lowest of the year.
If you are planning on climbing Mt Rinjani, this is the last month of the year to do so (before the rains arrive). It is also the last month for favourable dive conditions off the coast of Lombok, the Gili Islands and in the Komodo National Park.
Kalimantan is still enjoying predominantly dry, sunny days during October, although overcast skies tend to appear as the month rolls on with the imminent arrival of wet season. Humidity levels and average temperatures remain high and the mercury can hit 32°C on occasion.
October is typically one of the hottest months of the year across Sumatra with maximum temperatures of 32°C and 33°C the norm. Palembang and South Sumatra experience hot, sunny days, however in Medan and the north the rains arrive and heavy downpours can be expected, especially in the jungle-clad areas.
October is generally the hottest month of the year in Sulawesi and temperatures can frequently hit 34°C & 35°C at this time. Rainfall remains minimal, although in the island’s northern regions (including Manado), there is a higher chance of rain towards the end of the month. If you plan on diving in Manado Bay, October is the last month for favourable dive conditions.
Favourable weather conditions continue across the central islands of Ambon and Seram in October. The Banda Islands are also enjoying warm (28-30°C), sunny and dry days: October is an excellent time of year for diving in the Banda Islands. The story is different across the southern islands of Kei and Aru, and the northern islands of Ternate and Tidore as rainy season kicks in.
Favourable weather conditions can be expected across the islands of Raja Ampat and the Baliem Valley during October. Expect warm daily temperatures, good diving conditions in Raja Ampat and the occasional shower throughout the Baliem Valley.
From cruising the jungle waterways of Kalimantan’s rainforest and spotting orangutans, to soaking in the culture in Java to a few days relaxing on Bali and Komodo island - this is a trip full of beautiful contrasts in Java, Kalimantan, Bali and Komodo.