- BMKG warned that much of Indonesia could see light to very heavy rain on Saturday, with thunderstorms and strong winds possible in several major cities.
- The agency attributed the elevated risk to convergence and confluence patterns spanning parts of the Arafura Sea and Pacific waters near Halmahera and Papua.
- The central government urged local administrations in high-risk areas to activate disaster posts, as BMKG’s outlook flagged “alert” to “severe” rainfall risks for Jan. 23–25, including Banten, Jakarta and East Java.
The Meorology, Climatology and Geophysics Agency (BMKG) has issued an early warning for Saturday, citing the potential for light, moderate and heavy rain—possibly accompanied by lightning and strong winds—in a number of major Indonesian cities.
Quoting BMKG’s official website in Jakarta, forecaster Diah Ayu said a convergence zone is generally observed stretching across the southern Arafura Sea, South Papua, the northern Pacific Ocean off the west coast of Halmahera Island, and the western North Pacific waters off Papua.
Such conditions may increase the likelihood of rain cloud formation along areas affected by convergence or confluence, she added.
BMKG therefore forecasts that several major cities may see moderate to very heavy rain, accompanied by thunderstorms and strong winds, including Jakarta, Serang, Denpasar, Jayapura and Merauke.
Meanwhile, other major cities are expected to experience light to moderate rain, namely Tanjung Pinang, Palembang, Bandung, Semarang, Yogyakarta, Tanjung Selor, Mataram, Kupang, Mamuju, Makassar, Kendari, Manokwari, Nabire and Jayawijaya.
Several other major cities are forecast to be mostly cloudy on Saturday, including Banda Aceh, Medan, Pekanbaru, Jambi, Bengkulu, Bandar Lampung, Pangkal Pinang, Surabaya, Pontianak, Palangkaraya, Banjarmasin, Samarinda, Palu, Gorontalo, Manado, Ternate, Ambon and Sorong.
Earlier on Friday (Jan. 23), the central government urged provincial and regency/municipal administrations at the “alert” and “severe” levels for hydrometeorological disaster risk to activate disaster preparedness posts and emergency response command systems.
“BMKG’s early warning documents must serve as a direct reference for regional heads and all local government units in activating preparedness systems,” Coordinating Minister for Human Development and Culture Pratikno said.
BMKG has also published its national Early Weather Warning and a one-week outlook for the period of Jan. 23–29, 2026.
According to BMKG’s official document, several areas were classified from “alert” to “severe” for heavy to extreme rainfall during Jan. 23–25, 2026. For Jan. 23, 2026, BMKG set the “severe” level (very heavy–extreme rain) for Banten, Jakarta and East Java.
Indonesianpost.com | Antara