Penyebab Banjir Bali: BMKG Ungkap Peran Gelombang Rossby dan Curah Hujan Ekstrem

Summary

Bali faced severe flooding starting September 9, 2025, caused by heavy rainfall and extreme weather. Floodwaters submerged homes and public infrastructure, forcing evacuations, especially in Jembrana Regency and Denpasar City. Several areas, including Sanur, experienced roads transforming into rivers. A building collapse in Denpasar led to casualties. The Meteorology Agency attributed the storms to an active equatorial Rosby wave, which creates convective clouds and heavy rain. High air humidity and these atmospheric conditions intensified the rainfall, disrupting daily life across the region.

Takeaways

• 🌧️ Bali experienced severe flooding due to heavy rainfall starting Tuesday, September 9, 2025.
• 🏠 Floodwaters damaged infrastructure, submerged settlements, and forced residents to evacuate.
• 🌊 In Jembrana Regency, both homes and public facilities were affected by floodwaters.
• 🏢 Denpasar City was surrounded by floods from Wednesday, September 10, 2025, causing government offices and schools to close.
• 🏚️ A shop building in Tukad Badung, Denpasar, collapsed, resulting in three people being swept away.
• 🚗 In Monang Maning, drivers had to pull over as floodwaters threatened to stall vehicle engines.
• 🌊 Roads in Sanur turned into rivers due to the strong water flow.
• 🌡️ BMKG reported that the flooding was caused by extreme weather, specifically the active equatorial Rossby wave.
• ☁️ The Rossby wave promoted convective cloud growth, which led to heavy rainfall in the Bali region.
• 💧 High surface-layer humidity up to 500 mbar reinforced the extreme weather conditions, increasing rain cloud formation.

Q & A

What caused the flooding in Bali in September 2025?

The flooding in Bali was caused by heavy rain that began on Tuesday, September 9, 2025, which was intensified by an active equatorial Rossby wave and high air humidity.

Which areas in Bali were most affected by the floods?

Jembrana Regency, Denpasar City, Monang-Maning area, and Sanur were among the areas most affected by the floods.

What were some of the impacts of the floods on the local population?

The floods damaged infrastructure, submerged settlements, forced evacuations, closed government offices and schools, and caused a shop building to collapse, sweeping away three people.

What specific event happened at Tukad Badung in Denpasar during the floods?

A shop building on the edge of Tukad Badung collapsed during the floods, causing three people to be swept away.

How did the flooding affect transportation in Bali?

In the Monang-Maning area, drivers had to pull over to avoid stalling their engines, and in Sanur, roads turned into rivers due to strong water currents.

What explanation did BMKG give for the extreme weather in Bali?

BMKG explained that the extreme weather was caused by an active equatorial Rossby wave, which supports the growth of convective clouds and heavy rainfall, reinforced by high air humidity in the lower atmosphere.

Who provided the meteorological explanation for the floods?

Wayan Musteana, the head of the meteorological operational working group of BMKG Region 3, provided the explanation.

What are Rossby waves and how do they contribute to heavy rainfall?

Rossby waves are atmospheric waves that move westward around the equator. They can enhance the formation of rain clouds, which contributes to extreme weather events such as heavy rainfall.

When did flooding begin in Denpasar City according to the transcript?

Flooding in Denpasar City began on Wednesday morning, September 10, 2025.

What measures did residents take in response to the flooding?

Residents evacuated to safer locations, and drivers pulled over in high-risk areas to prevent vehicle damage due to floodwaters.