Jakarta—Heavy rainfall has recently hit various parts of Indonesia, triggered by two active tropical cyclones in southern Indonesian waters. The Meteorology, Climatology, and Geophysics Agency (BMKG) warned in a press release on Thursday, February 6, that this phenomenon could cause heavy to extreme rain, strong winds, and high waves in some areas.
“Currently, there are two active tropical cyclone seeds, namely Cyclone Seed 99S in the Indian Ocean south of Banten and Cyclone Seed 90S south of West Nusa Tenggara. Both affect the weather in Indonesia by increasing the intensity of rain and triggering strong winds and high waves,” said BMKG Head Dwikorita Karnawati.
According to BMKG analysis, as of February 2, 2025, these two cyclone seeds are predicted to move southwestward, further away from Indonesia. However, their indirect impact remains significant, especially in some areas with increasing rainfall and strong winds.
Extreme rain across Indonesia
According to BMKG data, the highest recorded rainfall occurred in several regions, with Jabodetabek experiencing the most significant downpour at 264 mm/day on January 28. East Kalimantan followed this at 229 mm/day and Central Sulawesi at 192 mm/day on January 26. The Riau Islands saw 154 mm/day on January 27, while East Java recorded 137.8 mm/day on January 29. Lastly, West Papua experienced 112 mm/day on January 31, highlighting intense rainfall patterns across different parts of Indonesia.
BMKG estimates that in the next week since February 2, some areas still have the potential to experience rain with moderate to very heavy intensity, which can even reach extreme levels.
Several regions in Indonesia need to remain vigilant due to potential extreme weather conditions. These include West Java, Central Java, East Java, and DI Yogyakarta, as well as the islands of West Nusa Tenggara (NTB) and East Nusa Tenggara (NTT). In Kalimantan, East Kalimantan and North Kalimantan are also at risk, while in Papua, heightened awareness is necessary across Papua, Papua Mountains, South Papua, West Papua, and Southwest Papua. Additionally, North Maluku and Jambi are among the areas that should be prepared for possible adverse weather impacts.
High waves threaten shipping activities
In addition to heavy rains, BMKG warned of the potential for high waves due to the influence of tropical cyclone seeds. Waves reaching 2.5 to 4.0 meters are predicted in several maritime regions, posing potential risks to navigation and coastal activities. These include the Indian Ocean, from the west of Bengkulu to Lampung, and from the south of Banten to NTT, as well as the Sawu Sea, Kupang Waters, and Rote Island.
Rough seas are also expected in the Maluku and Halmahera Seas, as well as in waters north of Southwest Papua to Papua. From north of Halmahera to Papua, the Pacific Ocean is also forecasted to experience similar wave conditions, highlighting the need for caution in these areas.
BMKG’s Deputy for Meteorology, Guswanto, added that fishermen and sea transportation operators must increase their awareness of these conditions. “We urge shipping activities, especially small vessels, to be more careful or postpone trips if necessary. Potential high waves in several waters can be dangerous for safety,” he said.
Threat of hydrometeorological disasters
BMKG also asked the public to increase preparedness for potential floods, landslides, and strong winds, especially in areas with vulnerable topographic conditions.
Dwikorita emphasised that people living in hilly areas and steep slopes should anticipate the potential for landslides, mainly when heavy rain occurs continuously. Some early signs of landslides that need to be considered include ground cracks, unusual water seepage, and trees or electricity poles that start to tilt.
In addition, drainage systems in urban areas must be checked to avoid flooding due to clogged drains.
“We ask all local governments and communities not to ignore these early warnings about extreme weather. Preparedness is the key to reducing the impact of disasters that can occur,” she added.
Local governments, disaster management agencies, and communities are asked to increase preparedness, especially for areas vulnerable to hydrometeorological disasters. Awareness and early anticipation are key in dealing with these increasingly erratic weather conditions. (Hartatik)
