REGIONAL SUMMARY:
For the thirty-third week of 2023, thirteen (13) disaster events reportedly affected the region. Indonesia and Thailand have been reportedly affected. Badan Nasional Penanggulangan Bencana (BNPB) of Indonesia reported floods and landslides in Aceh, West Sumatra, and North Sumatra; and drought in West and Central Java. Thailand’s Department of Disaster Prevention and Mitigation (DDPM) floods in Chiang Mai, Surat Thani, Satun, and Rayong Provinces.
HIGHLIGHT:
According to the BNPB Indonesia, heavy rainfall and unstable soil condition have resulted in flooding and landslides events in Pesisir Selatan, West Sumatra, particularly in Kecamatan XI Koto Tarusan and IV Jurai Painan on 17 August, and Kecamatan Silaut on 14 August. Based on the report, a total of 7.5K families (22.5K persons) were affected and damaged 3.6K houses. The Regent of Lumajang has declared an extension of the Emergency Response Status for a duration of 30 days (28 July – 26 August 2023). As of reporting, local disaster management authorities have carried out necessary actions to address the situation.
HYDRO-METEO-CLIMATOLOGICAL:
For the past week, data from the ASEAN Specialised Meteorological Centre (ASMC) showed high 7-day average rainfall spreading across north and central parts of Cambodia; central parts of Lao PDR; Peninsular, Sabah, and Sarawak Malaysia; coastal parts of Myanmar; central and norther pats of Sumatra, northern Kalimantan, and Papua in Indonesia; Mindanao of the Philippines; and southern parts of Viet Nam. As of reporting, INVEST 90W has persisted approximately 3,500 km east-northeast of Luzon in the Philippines. According to the global forecast model, INVEST 90W will slowly consolidate over the next 2 days and may move northwestward toward Japan (JTWC).
GEOPHYSICAL:
Four (4) significant earthquakes (M>5.0) were recorded by Indonesia’s Badan Meteorologi, Klimatologi, dan Geofisika (BMKG). Mount Dempo (alert level II), Ibu (alert level II), Semeru (alert level III), 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 the Philippine Institute of Volcanology and Seismology (PHIVOLCS).
OUTLOOK:
According to the ASEAN Specialised Meteorological Centre (ASMC), for the coming week, wetter conditions are expected over parts of Mainland Southeast Asia and the Philippines; drier conditions are expected over much of the central Maritime Continent; warmer conditions are expected over much of the Maritime Continent and northern Mainland Southeast Asia. For the regional assessment of extremes, there is a small increase in chance for a very heavy rainfall event to occur in the parts of Myanmar, Cambodia, and central Philippines; a small increase in chance in the coastal parts of the equatorial region and moderate increase in chance in the parts of central Myanmar and western Thailand for extreme hot conditions. El Niño conditions are predicted to strengthen over the next few months. At the seasonal timescale during June to August, El Niño events bring drier conditions to much of the southern ASEAN region.
Sources:
ASEAN Disaster Monitoring & Response System (DMRS); ASEAN Specialised Meteorological Centre (ASMC); Joint Typhoon Warning Centre (JTWC);
Indonesia: BNPB, BMKG, PVMBG;
Philippines: PHIVOLCS;
Thailand: DDPM;
Various news agencies.
