FLASH UPDATE #2 – Tropical Cyclone 13W and INVEST 92W
Country under monitoring: Cambodia, Lao PDR, Philippines, Thailand, and Viet Nam
CHRONOLOGY OF EVENTS:
- On 24 Sep, the Tropical Disturbance INVEST 91W over the Viet Nam East Sea has a HIGH potential to develop into a significant tropical cyclone within the next 24 hours (JTWC). According to NCHMF, on the afternoon of 24 Sep, the LPA (INVEST 91W) was located at 200 km southeast Hoang Sa archipelago and had developed into a Tropical Depression (TD) category. The TD continue to move generally west direction at 10 km/h.
- On 25 Sep, the TD continued to move west direction. On the evening of 25 Sep, the TD made its landfall over Quang Binh – Thua Thien Hue Provinces. The TD further continued to move west-northwestward across the area of Quang Bing – Thua Thuen Hue Provinces.
- On 26 Sep, early morning, the TD made its landfall over the central provinces of Lao PDR and further weakened into a low-pressure area.
IMPACTS:
- INVEST 91W: According to the latest available report from VDDMA, the provinces of Quang Binh, Quang Tri, and Thua Thien Hue have experienced heavy rain and thunderstorms. The severe weather conditions have led to 1 casualty and 1 injured person. The damages reported include 153 houses, with 69 houses in Quang Tri and 84 houses in Thua Thien Hue being affected. Additionally, flooding has been observed in several road sections.
- INVEST 92W: As of reporting, Tropical Disturbance INVEST 91W in the eastern parts of the Philippine Sea has dissipated. However, the Southwest Monsoon in the Philippines still persist. According to the NDRRMC, Regions VI, XII, and BARMM in the Philippines have been affected by floodings and landslides caused by the Intertropical Convergence Zone (ITCZ), the Southwest Monsoon, and a Low-Pressure Area (LPA). As of reporting, the disasters have resulted in 2 casualties, 1 missing person, 1 injured person, 81.9K families (391.9K persons) affected, and 2.4K persons displaced.
PRELIMINARY ANALYSIS:
According to DMRS and PDC-Global, an estimated 8.89 Million people, 2.83 Million households, and 107.92 Billion (USD) of infrastructure (total replacement value) are potentially exposed to moderate to severe damaging winds (with damage expected closer to the shores) with the following details:
- Viet Nam: 2.05M people, 597K households, and 3.34B (USD) of infrastructure (total replacement value) are exposed;
- Lao PDR: 1.28M people, 274K households, and 4.21B (USD) of infrastructure (total replacement value) are exposed;
- Cambodia: no forecast information is currently available for population and capital exposed;
- Thailand: 5.55M people, 1.95M households, and 100 Billion (USD) of infrastructure (total replacement value) are exposed;
ANTICIPATED RISK:
- According to the ASEAN Specialised Meteorological Centre (ASMC), wetter conditions are predicted over southern Mainland Southeast Asia for the period of 25 September – 1 October. For the regional assessment of extremes, there is a possibility for a very heavy rainfall event to occur in Southern Mainland Southeast Asia including Cambodia, Southern Lao PDR, Thailand, and Viet Nam;
- In Cambodia, according to MWRM for the period of 26-28 September, scattered heavy thundershowers are expected.
- In Lao PDR, according to DMH, several provinces, such as Houaphanh, Xieng Khouang, Luang Prabang, Xayaboury, Vientiane Capital, Xaysomboun, Vientiane, Bolikhamxay, Khammouane, Savannakhet, Salavanh, Champasack, Sekong, and Attapeu, may experience moderate to severe rainfall from 26-27 Sep.
- In the Philippines, according to PAGASA, high chances of rains over MIMAROPA and Western Visayas caused by the Southwest Monsoon are still expected. PAGASA also forecasts the TC-like vortices (TCLV) over the Philippine East Sea with a low to moderate likelihood of TC genesis. This TCLV is expected to enter the Philippine Area of Responsibility (PAR) while moving in a westerly direction during the period of 2-8 October.
- In Thailand, during the period of 26-28 September, heavy to very heavy rainfall is expected in several areas over Northern, Northeastern, Central, Eastern, and Southern Regions (TMD).
- In Viet Nam, NCHMF forecasted that heavy to very heavy rainfall is expected over the area from Thanh Hoa to Quang Binh; moderate to heavy rainfall, and several areas are very heavy rain with a maximum over 180 mm is expected over northern Delta and from Quang Tri to Quang Ngai; and moderate to heavy rain, and some areas are very heavy rain with a maximum over 120 mm over South Central, Central Highlands, and Southern Regions.
PREPAREDNESS AND RESPONSE:
- In Viet Nam, The National Steering Committee for Disaster Prevention and Control of Viet Nam has dispatched a letter No. 11/CD-QG dated 24 September 2023 to proactively respond to the potential impacts of 13W (VDDMA).
National Disaster Management Organisations (NDMOs) in exposed Member States currently closely monitor situations. - National Meteorological and Hydrological Services (NHMSs) in Cambodia (MWRM), Lao PDR (DMH), Philippines (PAGASA), Thailand (TMD), and Viet Nam (NCHMF) continue to monitor the weather situation and provision of weather updates to all stakeholders.
The AHA Centre will continue to monitor for further developments and issue necessary updates.
DATA SOURCES:
ASEAN Disaster Monitoring & Response System (DMRS);
Cambodia: MWRM;
Lao PDR: DMH
Philippines: NDRRMC; PAGASA;
Thainland: TMD;
Viet Nam: VDDMA, NCHMF;
Verified news media agencies.
