This page presents Indonesia's climate context for the current climatology, 1991-2020, derived from observed, historical data. Information should be used to build a strong understanding of current climate conditions in order to appreciate future climate scenarios and projected change. You can visualize data for the current climatology through spatial variation, the seasonal cycle, or as a time series. Analysis is available for both annual and seasonal data. Data presentation defaults to national-scale aggregation, however sub-national data aggregations can be accessed by clicking within a country, on a sub-national unit. Other historical climatologies can be selected from the Time Period dropdown list. Data for specific coordinates can be downloaded for in the Data Download page.
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.