REGIONAL SUMMARY:
During the thirty-fourth week of 2025, a total of 22 disaster events were recorded across ASEAN region, including an earthquake, droughts, floods, landslides, storms, and wind-related incidents affecting Indonesia, the Philippines, Thailand, and Viet Nam. In Indonesia, Badan Nasional Penanggulangan Bencana (BNPB) reported incidents in Jakarta, West Java, Central Java, East Java, Yogyakarta, Central Kalimantan, and Central Sulawesi. In the Philippines, the National Disaster Risk Reduction and Management Council (NDRRMC) reported flooding in Regions I, II, V, XII, CAR, NCR, and BARMM, caused by Tropical Cyclone KAJIKI and the Southwest Monsoon. Meanwhile, in Thailand, the Department of Disaster Prevention and Mitigation (DDPM) documented flooding, storms, and strong winds across Chiang Rai, Phetchabun, Chiang Mai, and Phra Nakhon Si Ayutthaya. In Viet Nam, Disaster and Dyke Management Authority (VDDMA) reported flooding and landslides affecting Son La, Thai Nguyen, Bac Ninh, and Dong Nai provinces.
HIGHLIGHT:
On 19 August, Low Pressure Area (LPA) was monitored outside the Philippine Area of Responsibility (PAR) and subsequently entered the PAR on 20 August. This LPA later intensified into a tropical depression, internationally named KAJIKI (locally named as “Isang” in the Philippines), and made landfall over Casiguran, Aurora. KAJIKI slightly decelerated as it traversed Quirino Province and moved west-northwestward across Ifugao Province. It then emerged over the waters west of the Ilocos Region, traversed the West Philippine Sea, and exited the PAR on 23 August. According to NDRRMC, as of 25 August, KAJIKI, in and the Southwest Monsoon, had affected approximately 11.4K families (50.7K) persons, across Regions II, CAR, V, XII, and BARMM. More than 30 flooding incidents were reported in the NCR and BARMM. Approximately 1.2K people are currently staying in 6 evacuation centres, while 24.1K people are taking shelter with relatives or in locations outside designated evacuation facilities.
KAJIKI continued moving west-northwestward toward mainland Southeast Asia. According to the NCHMF, KAJIKI (referred to locally in Viet Nam as Storm No. 5), at 1600 HRS UTC+7 was located over the coastal waters of Nghe An – Ha Tinh and was moving at a speed of 15–20 km/h in a west-northwest direction. According to VDDMA, the Government of Viet Nam had issued Official Dispatches No. 141/CD-TTg (dated 22 August 2025) and No. 143/CD-TTg (dated 23 August 2025), directing authorities to strengthen preparedness and response measures for KAJIKI and the associated flooding, to ensure the safety of lives and minimise damage to properties. The AHA Centre continues to closely monitor the situation and remains in close coordination with affected and potentially affected ASEAN Member States, stands ready to provide support if required.
HYDRO-METEO-CLIMATOLOGICAL:
For the past week, data from the ASEAN Specialised Meteorological Centre (ASMC) indicated high 7-day average rainfall concentrated across Brunei Darussalam, Cambodia, Indonesia, Lao PDR, Malaysia, Myanmar, the Philippines, Singapore, Thailand, and Viet Nam. In addition to Tropical Cyclone KAJIKI, which is currently affecting the ASEAN region, another Low Pressure Area (INVEST 93W) has been observed approximately 150 km east of Eastern Samar, the Philippines, and is being closely monitored for potential development into a significant tropical cyclone (PAGASA, JTWC).
GEOPHYSICAL:
Six (6) significant earthquakes (M>5.0) were recorded by Indonesia’s Badan Meteorologi, Klimatologi, dan Geofisika (BMKG), Myanmar’s Department of Meteorology and Hydrology (DMH), and Thai Meteorological Department (TMD). Mount Dempo (alert level II), Semeru (alert level II), Lewotobi Laki-laki (alert level III), Ibu (alert level II), and Ibu (alert level II) in Indonesia, and Kanlaon (alert level 2), 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 the Philippines Institute of Volcanology and Seismology (PHIVOLCS).
OUTLOOK:
According to the ASEAN Specialised Meteorological Centre (ASMC), for the coming week, warmer than usual temperatures are predicted over parts of the western Maritime Continent. For the regional assessment of extreme weather events, there is a small increase in chance of extreme hot conditions to occurs over southern Peninsular Malaysia, northern Sumatra. 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: DMH;
Philippines: NDRRMC, PAGASA, PHIVOLCS;
Thailand: DDPM, TMD;
Viet Nam: VDDMA, NCHMF;
Various news agencies.
