A total of 16 disasters (12 floods, 1 landslide, 2 wind-related, 1 storm) affected the region in the fourth week of 2021. Indonesia, Thailand, and Malaysia have been reportedly affected. As forecasted by the ASEAN Specialised Meteorological Centre (ASMC) wetter conditions were observed mostly in Java, Indonesia and caused flooding and landslide hazards as reported by the Badan Nasional Penanggulan Bencana (BNPB). Flooding was also reported in Sarawak State of Malaysia by the Agensi Pengurusan Bencana Negara (NADMA). Lastly, windstorms caused damages in Phrao District of Chiang Mai, Thailand as reported by the Department of Disaster Prevention and Mitigation (DDPM).
According to reports from the BNPB, heavy rainfall in West Nusa Tenggara, Indonesia resulted in localised flooding incidents. Flash floods have been reported in Sumbawa Regency. Meanwhile in West Lombok, the heavy rain increased discharge of the Telaga Lebur and Kelep Rivers. Lastly in Central Lombok, the heavy rainfall resulted in flooding. These events affected 1.7K families (6K people) and damaged 1.7K houses. According to latest reports, the rain has subsided, and the floods have started to recede. The BPBD in the respective regencies have also coordinated with relevant authorities and have conducted rapid assessments.
For the past week, data from the ASEAN Specialised Meteorological Centre (ASMC) showed high 7-day average rainfall over the southern ASEAN region. This is in accordance with ASMC‘s forecast for the past week. The wetter conditions, however, are expected to ease in the coming week. As of reporting, no tropical cyclone advisory has been issued by the JTWC.
Eight (8) significant earthquakes (M≥5.0) were recorded in the region by Indonesia’s Badan Meteorologi Klimatologi dan Geofisika (BMKG). Mt. Merapi, Sinabung, and Karangetang in Indonesia reported recent volcanic activity, all are on Alert Level III and are under close monitoring. Lastly, Raung and Dukono in Indonesia as well remain on Alert Level II despite recent volcanic activity per PVMBG.
For the coming week, the ASMC forecasts that the wetter and cooler conditions in the southern ASEAN region will ease and the wetter conditions to be confined in Java, Indonesia. For the regional assessment of extremes, there is a small increase in chance for a very heavy rainfall event to occur in parts around Java and Nusa Tenggara of Indonesia. There will be low chances of extended dry conditions, and extreme hot and cold conditions in the region.