BMKG Issues Hydrometeorological Disaster Alert Information

On October 20, 2025, the Sultan Iskandar Muda (SIM) Banda Aceh Class 1 Meteorological Station issued an early warning to the Governor of Aceh regarding Hydrometeorological Disaster Alert Information in Aceh. The following message was conveyed: in connection with the active Asian monsoon in the Aceh region and the presence of atmospheric disturbances, namely the Equatorial Rossby wave, the Dipole Mode Index value shows a value of -1.39, thus increasing convective patterns/activities, as well as the presence of wind bends (shearlines) and convergence in the Aceh region, some of these conditions can contribute to the process of rain cloud formation in the Aceh region.

Based on the Tropical Cyclone Warning Center (TCWC) Jakarta, the presence of tropical cyclone seeds 93B and also 95S was monitored which also contributed to increased rainfall, potential for strong winds, and increased sea wave height, here we convey Hydrometeorological Disaster Alert Information in the form of potential moderate to heavy rain accompanied by lightning and strong winds, which can cause disasters Strong winds, floods, landslides and other disasters in the attached area (Attachment 2). This was conveyed by Nasrol Adil, Head of the Class 1 SIM Meteorological Station.

BMKG Promotes Preparedness for the Peak Rainy Season in 2025-2026

The Head of the Aceh Climatology Station, Muhajir, S.Si, M.Si has previously also socialized the preparedness to face the peak of the 2025-2026 rainy season on October 6, 2025. The message is as follows: Based on the results of the Analysis and Prediction of the Rainy Season (PMH) 2025-2026 conducted by the Aceh Climatology Station of the Meteorology, Climatology and Geophysics Agency (BMKG), Aceh Province in general will enter the peak of the Rainy Season in the period of November and December 2025, and a small part in October 2025. During this period, most areas of Aceh are predicted to experience a significant increase in rainfall, especially in the South West Coast of Aceh, Central and East Aceh which have the potential to cause hydrometeorological disasters such as floods, waterlogging and landslides.

In this regard, BMKG urges the Aceh Government, and the City and District Governments together with related agencies and the community to increase preparedness and cross-sectoral coordination, especially in:

1. Mass media and public communication institutions should help optimize the dissemination of information from BMKG channels (Iklim.bmkg.go.id, the InfoBMKG application, and official social media) such as early warnings quickly, precisely and accurately to the public.
2. Ensure drainage channels, rivers and flood control infrastructure are in good condition.
3. Improve coordination between disaster-related institutions, including BPBA, TNI/Polri, and district/city authorities.
4. The Department of Agriculture and Plantations should disseminate weather and climate information to farmers to adjust cropping patterns.

For your consideration, the BMKG has also included information on the 2025-2026 rainy season forecast for Aceh Province as a basis for planning mitigation and preparedness measures in the region. Furthermore, the BMKG’s monthly Aceh Climate Bulletin for October 2025 has also been released.

Heavy Rain and Floods Have Started to Hit Aceh

At the time of writing, on October 24, 2024, Banda Aceh was experiencing cloudy skies all day and continuous rain. Flooding incidents had also begun to appear in various news reports. The west coast of Aceh, from Aceh Jaya, West Aceh, Nagan Raya, and South Aceh, was affected by flooding. This was predicted to be just the beginning, as heavy rainfall was expected in October. The Meteorology, Climatology, and Geophysics Agency (BMKG) predicted that rainfall would be very high in the area in November 2025. Mr. Muhajir also outlined this in more detail in a presentation delivered at an online press release meeting on the 2025/2026 Aceh rainy season predictions on September 30, 2025.

The Relationship between Accumulated Deforestation and Flooding

As we know, Aceh is a region with relatively good forest cover. More than half of its land area is covered by forest. However, Aceh has experienced significant forest cover loss, or deforestation. Cumulatively, the total amount of deforestation in Aceh is approximately 700,000 hectares from 1990 to today. This makes Aceh relatively vulnerable to hydrometeorological disasters. The book “Two Decades of Deforestation in Aceh,” compiled by the Aceh Central Statistics Agency (BPS), supported by HAkA, reveals the relationship between accumulated deforestation and the frequency of flooding. The higher the accumulated deforestation, the more frequent the flooding. Aceh’s remaining forests must be collectively maintained to reduce or even eliminate the frequency of flooding in Aceh.