OVERVIEW:According to NDMO Lao PDR, continuous heavy rainfall since the onset of Tropical Cyclone MAYSAK on 3 July 2026, combined with the prevailing monsoon rains, resulted to widespread flooding that affected 654 villages across 42 districts across Luang Nam Tha, Borkeo, Xaiyaboury, Borlikhamxay, Khammouane, Savannakhet, Sekong, and Champasak. Khammuoane and Champasak were reportedly the most severely affected provinces.
IMPACTS: The following impacts have been reported by NDMO Lao PDR as of 18 August 2026:
- 4 dead
- 95.2K people affected (20.1K families)
- 120 people displaced
- 15 damaged houses (10 totally damaged)
- 235 roads, 2 bridges affected
Data collection and assessments still ongoing.
HAZARDS & ANTICIPATED RISKS:
- According to the Department of Meteorology and Hydrology (DMH) of Lao PDR, a low pressure trough continues to pass over the northern and central parts of Lao PDR, combined with the prevailing Southwest Monsoon, which will bring light to moderate thunderstorms in all regions and heavy to very heavy rain in some areas, along with occasional strong winds. Heavy rainfall may trigger flash floods and landslides in susceptible areas across 13 provinces in Northern, Central, and Southern Lao PDR.
- According to ASMC, a moderate increase in extreme rainfall is predicted over Lao PDR and parts of northern Viet Nam for the period 17 to 23 August 2026. Moreover, wetter conditions are predicted over much of the Northern ASEAN region including most of Lao PDR.
- INVEST 95W, currently being monitored east of Hainan Island, combined with the strong Southwest Monsoon, will cause increased thunderstorms across the regions of Lao PDR. Heavy to very heavy rain is expected over the next three days in the northern, central, and southern provinces. (DMH)
- Prevailing Southwest Monsoon combined with the developing low pressure areas may also affect Thailand and Viet Nam.
PREPAREDNESS AND RESPONSE:
- NDMO Lao PDR is closely monitoring the situation and coordinating with the provincial disaster management offices.
- Damage assessments and data collection are underway in affected provinces.
- DMH continues to monitor the prevailing weather systems and provides regular updates and advisories.
The AHA Centre will continue to monitor the situation closely in coordination with the NDMO Lao PDR and issue updates as necessary. The AHA Centre stands ready to support the NDMO Lao PDR and other potentially affected ASEAN Member States should the need arise.
DATA SOURCES
ASEAN Disaster Monitoring & Response System (DMRS), ASEAN Disaster Information Network (ADINet); ASEAN Specialised Meteorological Centre (ASMC);
Lao PDR: NDMO, DMH;
Verified news media agencies
