Peak Rainy Season in November-December, BMKG Warns of Potential Galodo Marapi in West Sumatra

PADANG, KOMPAS — The Meteorology, Climatology, and Geophysics Agency, or BMKG, forecasts that the peak of the rainy season in West Sumatra will occur in November-December 2025. The public is also reminded of the potential for hydrometeorological disasters, including flash floods, due to heavy to extreme rainfall.

The Head of the Class II Minangkabau-Padang Pariaman Meteorological Station, Desindra Deddy, stated on Monday (10/11/2025) that based on climate conditions, the West Sumatra region is currently beginning to enter the rainy season. Rain has started to occur in various areas of the province, although the intensity has not yet been uniform.

"The peak of the rainy season will occur from November to December. Rainfall will increase. At its peak, there is a potential for heavy, even extreme, rain," he said on Monday afternoon.

Desindra explained that at the beginning of November, there was indeed an atmospheric dynamic that caused a lack of rainfall in several areas of West Sumatra, including the city of Padang, for a week. This condition was triggered by wind patterns that resulted in the absence of rain cloud formation. However, moving forward, conditions are beginning to normalize.

According to Desindra, to anticipate the peak of the rainy season, the public needs to increase their vigilance. For information updates, the public can access public weather information services on various BMKG channels, including Facebook, Instagram, and Twitter, as well as the Info BMKG app.

Desindra said the potential for heavy to extreme rainfall during the peak of the rainy season could trigger inundation and flooding, especially in urban and lowland areas. In highland areas, heavy to extreme rainfall could trigger landslides and flash floods, also known as galodo.

Desindra also highlighted the potential for lahar floods or mudflows around Mount Marapi. Although it is on alert status, the volcano in the Agam and Tanah Datar regencies still frequently erupts, causing accumulations of volcanic ash material around the summit.

"It is feared that during heavy, even extreme, rainfall, the accumulation of volcanic ash could trigger flash floods. Increased vigilance is necessary in the areas surrounding Marapi," he stated.

Regarding the potential disasters during the rainy season, Desindra stated that the Meteorology, Climatology, and Geophysics Agency (BMKG) has coordinated with the provincial and district/city Regional Disaster Management Agencies (BPBD). The National Police, through the West Sumatra Regional Police and the ranks of the Police Resort, have also conducted a disaster preparedness rally for hydrometeorological events.

"This is a concrete step by stakeholders to increase awareness regarding wet hydrometeorological disasters," said Desindra.

The spokesperson for the West Sumatra Regional Disaster Management Agency, Ilham Wahab, stated that the West Sumatra Provincial Government has declared a state of emergency alert in response to the potential threats of flooding, lahar floods, and landslides during the peak of the rainy season. This status is effective from September to December 2025. The declaration of this status responds to early warnings from the Meteorology, Climatology, and Geophysics Agency.

"Many efforts are being made during this state of emergency, particularly to enhance coordination with districts/cities to remain vigilant in areas prone to flooding, lahar rain floods, and landslides," he said.

According to Ilham, the West Sumatra BPBD also encourages the district/city BPBDs to socialize disaster potential to the community, especially those residing in flood-prone areas, lahar floods, and landslides.

"For residents living near the river that originates from Mount Marapi, it is important to increase vigilance regarding the potential for cold lahar floods," said Ilham.

Regarding disaster management equipment, Ilham stated that heavy equipment is on standby at several agencies, such as the Public Works Department, the Natural Resources and Resources Agency (SDABK), and the national road implementation center. If needed, the Regional Disaster Management Agency (BPBD) simply coordinates. "We've held several coordination meetings before," he said.