REGIONAL SUMMARY:
In the forty-first week of 2023, the ASEAN region experienced 8 disaster events that affected Indonesia, Malaysia, the Philippines, and Viet Nam. In addition to these, Department of Disaster Prevention and Mitigation (DDPM) Thailand also reported disaster events that began in week 39 and continued into week 41. In Indonesia, Badan Nasional Penanggulangan Bencana (BNPB) reported droughts in Bandar Lumpung (Lampung) and Takalar (South Sulawesi) and flooding events in Aceh Singkil (Aceh) and Pasaman (West Sumatra). In Malaysia, Agensi Pengurusan Bencana Negara (NADMA) reported landslides in Cameron Highlands (Pahang). Lastly, flooding was also reported by the National Disaster Risk Reduction and Management (NDRRMC) and Department of Social Welfare and Development (DSWD) in the Philippines’ Regions VI and XI and Viet Nam Disaster and Dyke Management Authority (VDDMA) reported in Viet Nam’s Central region.
HIGHLIGHT:
From October 9 to 15, the Southwest Monsoon as well as the trough of low pressure area in the eastern part of the Philippine Area of Responsibility continued to cause several flooding and landslide events in the region (DSWD). In Thailand, the latest report from the Department of Disaster Prevention and Mitigation (DDPM) reported 37 flood-affected provinces from the previously reported 20 provinces in week 39, with 61.7k affected families or 308.5k affected persons. According to VDDMA, the continuous rains also resulted to heavy flooding in the Central Region of Viet Nam that caused 2 casualties, affected 1.6k families (7.8k persons) and displaced 3.9k persons. Relevant government authorities have taken necessary actions to address the situation, including mobilising personnel and logistics for the affected community.
HYDRO-METEO-CLIMATOLOGICAL:
For the past week, the data from the ASEAN Specialised Meteorological Centre (ASMC) showed moderate to high 7-day average rainfall spreading across the region above the equatorial line (Brunei Darussalam, Cambodia, northern Sumatra, Kalimantan, and Papua in Indonesia, Southern Lao PDR, Malaysia, Myanmar, Visayas and Mindanao islands in the Philippines, western to southern parts of Thailand, and Viet Nam). Heavy rainfall concentration was observed in Central Viet Nam particularly with the formation of Tropical Disturbance INVEST 99W which was monitored East-Southeast of Hue, Viet Nam (JTWC). Global ensemble models and the GFS deterministic model have INVEST 99W slowly developing over the next 2 days with a possibility of landfall over Central Region on October 18. The NCHMF has issued a warning that heavy rainfall, tornadoes, and strong winds are expected to occur over the Viet Nam East Sea, including the Hoang Sa and Truong Sa archipelagos.
GEOPHYSICAL:
Five (5) significant earthquakes (M>5.0) were recorded by Indonesia’s Badan Meteorologi, Klimatologi, dan Geofisika (BMKG) and the Philippine Institute of Volcanology and Seismology (PHIVOLCS). Semeru (Alert Level III), Ibu (Alert Level II), and Ili Lewotolok (Alert Level II) in Indonesia; and Mayon (Alert Level 3), Taal (Alert Level 1), and Kanlaon (Alert Level 1) in the Philippines reported recent volcanic activity according to Indonesia’s Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) and PHIVOLCS.
OUTLOOK:
According to the ASEAN Specialised Meteorological Centre (ASMC), for the coming week, drier conditions are predicted over most of the southwestern Maritime Continent while wetter conditions are expected over most of Mainland Southeast Asia in 16-22 October. Warmer than usual temperature is predicted over most of Maritime Continent in this period. There is a moderate increase in chance for heavy rainfall over northeast Mainland Southeast Asia, including northern Thailand, northern Lao PDR, and northern Viet Nam and a small increase in chance for very heavy rainfall around the mentioned regions, covering southern Myanmar, southern Lao PDR, central and eastern Thailand, and northern Cambodia. There is an increased chance in in extreme hot conditions over the southern Maritime Continent, with moderate increase in chance over southern Sumatra and very likely over Java and Nusa Tenggara, and in the Philippines a moderate increase in chance of extreme hot conditions over the central region and small increase in chance over the southern region.
Sources:
ASEAN Disaster Monitoring & Response System (DMRS); ASEAN Specialised Meteorological Centre (ASMC); Joint Typhoon Warning Centre (JTWC);
Indonesia: BNPB, BMKG, PVMBG;
Malaysia: NADMA;
Philippines: NDRRMC, PAGASA, PHIVOLCS
Thailand: DDPM;
Viet Nam: VDDMA, NCHMF;
Various news agencies.