Indonesia flagClimate & Weather Guide

Climate zones, seasonal temperatures, rainfall patterns, and best travel times in Indonesia

Indonesia, an archipelagic nation spanning the equator, features a predominantly tropical climate with minimal seasonal temperature variation due to its location. Classified mainly under Köppen's Af (tropical rainforest), Am (tropical monsoon), and Aw (tropical savanna) types, it experiences high humidity, abundant rainfall, and warm temperatures year-round, ideal for expats seeking consistent warmth but challenging due to heavy rains and humidity. Recent BMKG forecasts for 2026 project annual rainfall between 1500-4000mm, with rainy seasons covering most regions from November to March, and potential tropical cyclones in southern areas. Sunshine is plentiful outside peak rains, averaging over 2500 hours annually, though high humidity (70-90%) persists. Residents should prepare for flooding in wet periods and leverage dry spells for outdoor activities.

Summer Average

26-32°C

Winter Average

24-30°C

Climate Types

Tropical Rainforest and Tropical Monsoon and Tropical Savanna

Annual Rainfall

1500-4000 mm

Sunshine Hours

2,500-3,200 hours annually

Average Humidity

70-90%

Regional Climate Variations

Western Sumatra and Java

This densely populated region, including Sumatra's west coast and Java, falls under tropical rainforest (Af) and monsoon (Am) climates with very high rainfall exceeding 2500mm annually, peaking November-March. Temperatures stay warm at 24-31°C year-round, with high humidity amplifying the muggy feel. BMKG notes elevated cyclone risks in southern areas like Bengkulu, bringing intense, prolonged rains that can cause floods and landslides. Dry periods are shorter, but orographic effects from mountains boost precipitation. Expats appreciate urban amenities in Jakarta and Bandung but must invest in flood-proof housing and air conditioning.

Summer:25-31°C
Winter:24-30°C
Very high rainfall

Oppressively humid with frequent heavy downpours; lush greenery but prepare for waterlogged streets and mold in homes during extended rainy seasons.

Kalimantan (Borneo)

Indonesia's share of Borneo features vast tropical rainforest (Af) climate, with extreme rainfall often over 3000mm yearly and temperatures 24-32°C consistently. Rainy season dominates from November to April, with BMKG forecasting normal 2026 patterns but high precipitation potential. Interior areas see less variation but higher humidity (80-95%). Expats in cities like Balikpapan enjoy biodiversity but face challenges from remoteness, poor drainage, and malaria risks in wet months. Dry spells allow for eco-tourism, though wildfires occasionally occur in prolonged droughts.

Summer:25-32°C
Winter:24-31°C
Very high rainfall

Sweltering rainforest humidity with daily afternoon storms; ideal for nature lovers but demanding AC, dehumidifiers, and elevated living to combat flooding.

Sulawesi and Maluku Islands

These rugged islands blend tropical rainforest (Af) and savanna (Aw) zones, with annual rainfall 2000-3500mm and steady warmth of 25-31°C. Rainy periods span late 2024 into 2026 per BMKG, affecting 75% of zones, while eastern coasts are slightly drier. Monsoon winds bring variability, with cyclone potential in Maluku. Expats value the scenic diving spots and cultural diversity but note infrastructure gaps, making power outages common during storms. Moderate sunshine supports outdoor lifestyles outside peaks.

Summer:25-31°C
Winter:24-30°C
Very high rainfall

Tropical island paradise with warm breezes and sudden squalls; vibrant marine life thrives, but slippery trails and boat safety are key concerns for residents.

Eastern Indonesia (Papua, Nusa Tenggara)

Eastern extremes contrast with drier tropical savanna (Aw) in Nusa Tenggara and wetter rainforest (Af) in Papua, rainfall 1500-3500mm. Temperatures 24-32°C show little change, but highlands in Papua cool to 20°C nights. BMKG highlights cyclone risks in south Papua and Nusa Tenggara during December-February. Bali offers a tourist-friendly microclimate with more sun. Expats flock to Bali for its balance but find remote Papua adventurous yet logistically tough due to heavy rains and isolation.

Summer:25-32°C
Winter:23-31°C
High rainfall

Drier east with sunny spells contrasting Papua's deluges; perfect for beach living in Bali, but highlands offer relief from lowland steaminess.

Indonesia's equatorial tropical climate delivers year-round warmth (24-32°C) with very high rainfall (1500-4000mm), varying from rainforest drench in Sumatra-Kalimantan to slightly drier savannas in the east. Expats enjoy endless summer vibes, biodiversity, and beaches but must adapt to humidity, monsoons, and flood risks via resilient homes and monitoring BMKG alerts. Ideal for heat-tolerant residents seeking adventure over four distinct seasons.