For the twenty-fifth (25th) week of 2021, a total of 9 disasters (5 floods, 3 wind-related, and 1 storm) affected the region. Indonesia, the Philippines, and Thailand have reportedly been affected. Several localized heavy rainfall which caused flooding and wind-related events occured in Indonesia as reported by Badan Nasional Penanggulangan Bencana (BNPB). Heavy rains brought by the Inter-Tropical Convergence Zone (ITCZ) caused flooding in Bagumbayan, Sultan Kudarat as reported by the National Disaster Risk Reduction and Management Council (NDRRMC). The Department of Disaster Prevention and Mitigation (DDPM) of Thailand reported winds and storms in Nong Bua Lam Phu, Roi Et, and Surin Provinces.
On 24 June, according to the BNPB, heavy rain caused the Keloam River and Semajit River to overflow in Pamekasan Regency. The flood reportedly affected around 1.5K households (6K people). The local disaster management agency was able to conduct a rapid assessment, evacuation of victims, and distribution of food relief. As of an update from 27 June, floods in the regency have reportedly receded.
For the past week, data from the ASEAN Specialised Meteorological Centre (ASMC) showed sporadic to sparse medium to high 7-day average rainfall mostly across the westernsouthwestern portion of the region (Sumatra, and Western Java, and western coasts of Mainland Southeast Asia). As of reporting, there is no tropical cyclone advisory by JTWC.
Four (4) significant earthquakes (M≥5.0) were recorded in the region by Indonesia’s Badan Meteorologi Klimatologi dan Geofisika (BMKG) and the Philippine Institute of Volcanology and Seismology (PHIVOLCS). Merapi and Ili Lewotolok in Indonesia (alert level III) and Taal Volcano in the Philippines (alert level 2) reported recent volcanic activity and are under close monitoring. Volcanic activity was also reported for Mount Semeru, Ibu and Dukono in Indonesia according to PVMBG and PHIVOLCS.
According to the ASMC, the following subseasonal conditions have been forecast wetter conditions for the southern parts of the Maritime Continent;
Drier conditions for much of the Northern ASEAN region; and warmer temperatures for much of 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 Southern Sumatra, western Java regions, southern Borneo, Sulawesi, Maluku Islands, and Nusa Tenggara in Indonesia; moderate increase in chance for extended dry conditions in Southern Myanmar, Thailand, most of Lao PDR, Cambodia, and Viet Nam; moderate increase in chance for extreme hot conditions in Southern Myanmar, Java Island, and Nusa Tenggara and very likely extreme hot conditions in Thailand, Lao PDR, Cambodia, and Northern Viet Nam.