Indonesia braces for heavy rains as atmospheric conditions favor storm development

Indonesia's Meteorology, Climatology, and Geophysics Agency (BMKG) predicts a high chance of heavy to very heavy rainfall across various regions on Thursday, June 11, 2026. The agency attributes this to atmospheric conditions, specifically the formation of wind slowdown zones, known as convergence.

According to BMKG forecaster Nazmi Nariyah, these convergence zones stretch from West Sumatra, Jambi, South Sumatra, across Kalimantan, Sulawesi, Maluku, and extending to Papua. Additionally, wind confluence, or the meeting of winds, is expected in areas like the Andaman Sea, Malacca Strait, South China Sea, Sulu Sea, and the Pacific Ocean north of Papua. These atmospheric patterns are conducive to the development of rain clouds.

Residents in many major Indonesian cities are advised to remain vigilant. The BMKG forecasts potential thunderstorms and lightning in Tanjung Pinang, Pontianak, and Banjarmasin. Lighter rain is expected in Medan, Pangkal Pinang, Palangka Raya, Samarinda, and Tanjung Selor. Jakarta, Banda Aceh, Serang, Bandung, and Surabaya are predicted to experience thick cloud cover.

In eastern Indonesia, heavy rain is anticipated in Mamuju, thunderstorms in Ternate, moderate rain in Ambon, and light rain in numerous other cities, including Denpasar, Makassar, and Jayapura. The BMKG's forecast highlights the widespread impact of these weather patterns across the archipelago.