REGIONAL SUMMARY:
In the twenty-first week of 2025, the ASEAN region experienced a total of 38 significant disasters, including floods, landslides, earthquakes, and wind-related disasters, which affected Indonesia, Thailand, and Viet Nam. In Indonesia, Badan Nasional Penanggulangan Bencana (BNPB) reported impacts of these events in Maluku, Central Java, West Java, East Java, North Kalimantan, Riau, West Sulawesi, North Sulawesi, Bengkulu, North Sumatra, Aceh, Jakarta, Banten, and North Maluku. Thailand’s Department of Disaster Prevention and Mitigation (DDPM) reported storms, strong winds, and floods in the provinces of Chaiyaphum, Krabi, Uthai Thani, and Tak. In Viet Nam, the Viet Nam Disaster and Dyke Management Authority (VDDMA) reported storms, floods, and landslides in Ha Tinh and the provinces of Lao Cai, Yen Bai, Tuyen Quang, Cao Bang, and Bac Kan in the Northern Region. Meanwhile, the National Disaster Risk Reduction and Management Council (NDRRMC) reported increasing impacts of the flooding that persisted from Week 20 in Maguindanao del Sur in BARMM, Philippines.
HIGHLIGHT:
In the Philippines, the Inter-Tropical Convergence Zone (ITCZ) continued to bring moderate to heavy rainfall over Mindanao. According to the NDRRMC, the widespread flooding in the province of Maguindanao del Sur that began in Week 20 had persisted in Week 21. According to NDRRMC’s Progress Report No. 5, the displaced population had reached 316.2K (63.2K families). A province-wide state of calamity was declared in Maguindanao del Sur as communities remain inundated by the prolonged flooding. NDRRMC-OCD Regional Office maintains Blue alert as authorities continue 24/7 operation to closely monitor and respond to the effects of the ITCZ.
Additionally, updated impact information on the M7.7 Mandalay Earthquake in Myanmar, based on DDM Myanmar report as of 26 May at 18:30 hrs UTC+7, indicates that a total of 3,731 fatalities have been recorded, with 71 individuals missing and 5,104 others injured. Approximately 506,069 people have been affected, including 26.2K displaced persons currently residing in 103 evacuation centres, and 265.1K individuals who have sought shelter with relatives. Reported damages include the approximately 51.2K houses (totally damaged) and over 39.6K houses (partially damaged), 2,598 schools, 748 hospitals, 10,372 offices and other buildings, as well as over 101 bridges and 419 roads. The estimated economic losses are approximately USD 1.8 billion. Data collection and validation are ongoing.
HYDRO-METEO-CLIMATOLOGICAL:
For the past week, data from the ASEAN Specialised Meteorological Centre (ASMC) indicated medium to high 7-day average rainfall across Brunei Darussalam, Cambodia, Indonesia (Sumatra, Java, Kalimantan, Maluku, Sulawesi, and Papua), Lao PDR, Malaysia, Myanmar, southern Philippines, Singapore, Thailand, and Viet Nam. As of this reporting period, there is no active tropical cyclone warning being monitored in the region (JTWC).
GEOPHYSICAL:
Four (4) significant earthquakes (M>5.0) were recorded by Indonesia’s Badan Meteorologi, Klimatologi, dan Geofisika (BMKG), Myanmar’s Department of Meteorology and Hydrology (DMH), Thailand Meterological Department (TMD), and the Philippine Institute of Volcanology and Seismology (PHIVOLCS). Mount Ibu (alert level II), Dukono (alert level II), Lewotobi Laki-laki (alert level III), Semeru (alert level II), Ili Lewotolok (alert level II), and Marapi (alert level II) in Indonesia, and Kanlaon (alert level 3), Taal (alert level 1), Mayon (alert level 1), and Bulusan (alert level 1) volcanoes in the Philippines reported recent volcanic activity according to Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) and PHIVOLCS.
OUTLOOK:
According to the ASEAN Specialised Meteorological Centre (ASMC), for the coming week, wetter conditions are predicted for western and central Mainland Southeast Asia. Meanwhile, for the Maritime Continent, drier conditions are predicted over the western and central equatorial region. Warmer than usual temperatures are predicted over much of the equatorial region. For the regional assessment of extremes, there is a moderate increase in chance of very heavy rainfall is predicted over parts of central and western Myanmar. There is also a small increase in chance of very heavy rainfall over parts Nusa Tenggara Islands. A moderate increase in chance of extreme hot conditions is predicted for most parts of the equatorial region. ENSO neutral conditions are present.
Sources:
ASEAN Disaster Monitoring & Response System (DMRS); ASEAN Specialised Meteorological Centre (ASMC); Joint Typhoon Warning Centre (JTWC);
Indonesia: BNPB, BMKG, PVMBG;
Myanmar: DDM, DMH;
Philippines: NDRRMC, PHIVOLCS;
Thailand: DDPM, TMD;
Viet Nam: VDDMA;
Various news agencies.
