'Bediding' Phenomenon Hits Java, Dieng Records Coldest Temperature
Lately, many social media users have complained that air temperatures feel colder, especially at night through to the early morning. The phenomenon, commonly known as ‘bediding’, typically occurs during the dry season and is felt across several regions of Java Island.
The Meteorology, Climatology, and Geophysics Agency (BMKG) explained that the cold temperature phenomenon is influenced by several factors, one of which is the strengthening of the Australian monsoon. These monsoon winds carry dry air masses that can reduce moisture content and cloud formation in the atmosphere.
The minimal cloud cover allows heat from the Earth’s surface to escape more easily into the atmosphere at night. As a result, air temperatures can drop quite significantly, especially towards the early morning.
“BMKG data from the last 10 years shows that the temperature drop begins to be felt in July and peaks between July and August. For example, in Malang Regency, temperatures can drop to below 19.5 degrees Celsius, far colder than Jakarta, which remains relatively stably warm,” BMKG stated, as quoted from its official Instagram account on Monday (27/7/2026).
“This also demonstrates the role of topography and highland elevation in trapping cold air,” BMKG added.
Observations from night-time Land Surface Temperature (LST) maps from the MODIS sensor on weather satellites also show a low-temperature zone stretching along the mountain ranges of Java Island. This indicates that mountainous areas are the regions most affected by the bediding phenomenon.
Similarly, Dr Givo Alsepan, a lecturer at the Department of Geophysics and Meteorology, Faculty of Mathematics and Natural Sciences (FMIPA) at IPB University, estimated that this phenomenon has the potential to continue until the peak of the dry season, around late July to August, and may even persist until early September in some regions, depending on atmospheric conditions.
“Indonesia is currently in the dry season influenced by the Australian monsoon, while Europe, North America and parts of East Asia are entering summer,” he explained, as quoted from the IPB website.
Areas Where It Is Most Felt
Meanwhile, BMKG said a number of highland areas have even experienced extremely low temperatures, such as Mount Bromo and Dieng.
“BMKG AWS data recorded the temperature at Bromo reaching 3.9 degrees Celsius on 11 June. But Dieng is the champion, with temperatures nearly touching freezing point at 0.7 degrees Celsius,” BMKG said.
“The bediding phenomenon is so cold that in highland areas such as Mount Bromo, dew clinging to leaves can freeze into ice crystals, resembling a blanket of snow,” BMKG added.
Tips for Facing Bediding 2026
So, what should be done to keep the body healthy and fit? BMKG has issued two recommendations for facing bediding:
Ensure adequate intake of nutrition and warm drinks. As a result, the body’s immunity is maintained.
Use moisturiser to prevent dry and cracked skin.