REGIONAL SUMMARY:
During the twenty-second week of 2026, a total of 30 disaster events were reported across the ASEAN region, including droughts, floods, landslides, storms, and wind-related disasters in Indonesia, Malaysia, the Philippines, Thailand, and Viet Nam. In Indonesia, Badan Nasional Penanggulangan Bencana (BNPB) reported disaster events across Banten, Gorontalo, Jakarta, West Nusa Tenggara, South Sulawesi, Central Sulawesi, North Sulawesi, and North Sumatra. In Malaysia, Agensi Pengurusan Bencana Negara (NADMA) reported storms and winds in Kuala Lumpur and Terengganu. In the Philippines, National Disaster Risk Reduction and Management Council (NDRRMC) and Department of Social Welfare and Development (DSWD) reported flooding in Region XII and effects of Tropical Cyclone JANGMI in BARMM. Meanwhile, in Thailand, Department of Disaster Prevention and Mitigation (DDPM) reported flooding, storms, and wind-related disasters in Nong Bua Lamphu, Phang Nga, Mae Hong Son, Lampang, Tak, Chiang Rai, Phetchabun, Chaiyaphum, Amnat Charoen, and Rayong. Lastly, in Viet Nam, Viet Nam Disaster and Dyke Management Authority (VDDMA) reported storms and winds in Lao Cai, Tuyen Quang, Son La, Dak Lak, Lam Dong, and Ca Mau.
HIGHLIGHT:
In the Philippines, Tropical Cyclone JANGMI (locally named “Domeng”) developed into a tropical depression over the western Pacific Ocean on 26 May. On 28 May, JANGMI intensified into a tropical storm and entered the Philippine Area of Responsibility (PAR), continuing to move northwestward. Although JANGMI is not make landfall over the Philippine landmass and was forecasted less likely to directly affect the weather conditions of the Philippines, the southwesterly wind flow enhanced by JANGMI may bring heavy rainfall to the western portions of the Philippines. As of 31 May at 0700 HRS (UTC+7), NDRRMC reported flooding in 37 areas across BARMM. The flooding affected and displaced approximately 17.1K families (85.3K persons) outside evacuation centres. Relevant authorities continue to provide immediate assistance to affected communities, while damage assessments and data collection remain ongoing. The AHA Centre continues to closely monitor the situation and remains ready to provide assistance should the need arise.
HYDRO-METEO-CLIMATOLOGICAL:
For the past week, data from the ASEAN Specialised Meteorological Centre (ASMC) indicated medium to high seven-day average rainfall across Brunei Darussalam, Cambodia, Indonesia, Lao PDR, Malaysia, Myanmar, Singapore, the Philippines, Thailand, and Viet Nam. During the reporting period, Tropical Cyclone JANGMI over the western Pacific Ocean was forecast to continue moving north-northwestward and was not expected to make landfall over the Philippine landmass (PAGASA, JTWC).
GEOPHYSICAL:
Seven (7) significant earthquakes (M>5.0) were recorded by Indonesia’s Badan Meteorologi, Klimatologi, dan Geofisika (BMKG) and the Philippines Institute of Volcanology and Seismology (PHIVOLCS). Mount Marapi (alert II), Semeru (alert level III), Lewotobi Laki-laki (alert level III), and Ibu (alert level II) in Indonesia, and Taal (alert level 1), Mayon (alert level 3), Bulusan (alert level 1), and Kanlaon (alert level 2) 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 forecast over parts of the northeastern Maritime Continent and much of Mainland Southeast Asia, while drier conditions are expected over much of the eastern Maritime Continent and the western half of the equatorial region. For assessment of extreme, there is a small increase in chance of extreme rainfall over parts of southwestern Mainland Southeast Asia including southern Myanmar and southern Thailand, as well as parts of northern Philippines; and there is a moderate increase in chance of extreme hot conditions over parts of the western Maritime Continent, including the southern Malay Peninsula and northeastern Sumatra. A transition to El Nino conditions is predicted in June- July 2026.
Sources:
ASEAN Disaster Monitoring & Response System (DMRS); ASEAN Disaster Information Network (ADINet); ASEAN Specialised Meteorological Centre (ASMC); ASEAN Earthquake Information Centre (AEIC); Joint Typhoon Warning Centre (JTWC);
Indonesia: BNPB, BMKG, PVMBG;
Malaysia: NADMA,
Philippines: NDRRMC, PAGASA, DSWD, PHIVOLCS;
Thailand: DDPM, TMD;
Viet Nam: VDDMA;
Various news agencies.
