REGIONAL SUMMARY:
In the twenty-second week of 2025, the ASEAN region experienced a total of 35 significant disasters, including floods, landslides, earthquakes, and wind-related disasters, which affected Indonesia, the Philippines, Thailand, and Viet Nam. In Indonesia, Badan Nasional Penanggulangan Bencana (BNPB) reported impacts of these events in East Java, Banten, Central Sulawesi, East Kalimantan, Southeast Sulawesi, South Sumatra, North Sumatra, Aceh, South Sulawesi, Jembrana, West Java, and Riau. In the Philippines, the National Disaster Risk Reduction and Management Council (NDRRMC) reported storms, landslides, strong winds, and flooding in the provinces of Region XII as well as increasing impacts of the flooding that persisted from Week 20 in BARMM. Thailand’s Department of Disaster Prevention and Mitigation (DDPM) reported storms, strong winds, floods, and landslides in the provinces of Lampang, Chiang Mai, Tak, Loei, Chaiyaphum, Phetchabun, and Nakhon Si Thammarat. In Viet Nam, the Viet Nam Disaster and Dyke Management Authority (VDDMA) reported storms, floods, and landslides in Nghe An and Ha Tinh in the Central Region.
HIGHLIGHT:
In Indonesia, the BNPB reported a landslide that occurred in a mining area in Cipanas Village, Cirebon Regency in West Java on 30 May. A joint team of local authorities, Basarnas, volunteers, and community members immediately responded and conducted search and rescue operations. According to BNPB’s report on 1 June, recorded casualties had reached 19 fatalities, 6 missing, and 8 injured. In addition, four units of heavy excavators and seven units of trucks were buried by landslides.
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 extended to Maguindanao del Norte, Basilan, and Sulu provinces, also in BARMM. According to NDRRMC’s Progress Report No. 7, the displaced population had reached 370.9K (74.2K families). A province-wide state of calamity was declared in Maguindanao del Sur (24 municipalities) as communities remain inundated by floods. NDRRMC-OCD Regional Office maintains Blue alert as authorities continue 24/7 operation to closely monitor and respond to the effects of the ITCZ.
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, eastern parts of Lesser Sunda, and Papua), Lao PDR, Malaysia, Myanmar, the Philippines, Singapore, Thailand, and Viet Nam. Notable areas with high average rainfall were the vicinities of the Bay of Bengal and West Philippine Sea, where low pressure areas INVEST 94B and INVEST 91W, developed and eventually dissipated. 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) and the Philippine Institute of Volcanology and Seismology (PHIVOLCS). Mount Ibu (alert level II), Dukono (alert level II), 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, drier than usual conditions for this time of the year are predicted for western and central Mainland Southeast Asia while wetter conditions are predicted over parts of the southern Maritime Continent. Warmer than usual temperatures are predicted over much of the equatorial region and over the northeastern parts of Mainland Southeast Asia. For the regional assessment of extremes, there is a small increase in chance of very heavy rainfall predicted over Nusa Tenggara Islands. Meanwhile, there is also a small increase in chance of extreme hot conditions over the equatorial region and parts of northeastern Mainland Southeast Asia, including northern Viet Nam and northeastern Lao PDR. 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;
Philippines: NDRRMC, PHIVOLCS;
Thailand: DDPM;
Viet Nam: VDDMA;
Various news agencies.
