Indonesia’s climate is largely hot and humid, with rainfall occurring mostly in low-lying areas and mountainous regions experiencing cooler temperatures. The cities of Jakarta, Ujung Padang, Medan, Padang, and Balikpapan have an average minimum temperature of 22.8°C and a high of 30.2°C. Humidity in Jakarta varies between 61% to 95% and average rainfall amounts to 218.4 millimeters (mm) per month. The “wet” season occurs between November and April, leaving May through October typically dry. Indonesia experiences drier conditions during El Nino events and wetter conditions during La Nina events. Indonesia lies across the range of the Inter-Tropical Convergence Zone (ITCZ) where the northeast and southeast trade winds penetrate the doldrums. Strong ascending motion, overcast skies, strong squalls, heavy rainfall and severe local thunderstorms with variable intensities are characteristics of this zone.
- Since 1990, mean annual temperature has increased by about 0.3°C.
- Overall annual rainfall has decreased by 2-3% since 1990.
- Precipitation patterns have changed - particularly during the wet and dry seasons. There has been a decline in average annual rainfall in the southern regions (though this includes increases in wet season rainfall), while an average increase in precipitation in the northern regions is coupled with decreased dry season rainfall.
This section provides the options to visualize historical climate data for different timeframes via map and annual cycle chart.