FLASH UPDATE #1 – Tropical Disturbance INVEST 91W, 92W, and Southwest Monsoon
Country under monitoring: Cambodia, Lao PDR, Philippines, Thailand, and Viet Nam
INVEST 91W
OVERVIEW: The area of convection INVEST 91W located near 14.8N 112.4E, approximately 384 east of Quang Ngai, Viet Nam. According to NCHMF, the Low-Pressure Area (LPA) in the southeast sea of Hoang Sa archipelago has strengthened into a tropical depression as of 1300 HRS UTC+7. The location the tropical depression was about 200 km southeast of Hoang Sa archipelago.
INTENSITY: According to NCHMF, the strongest wind near the center of the tropical depression is strong at about 39-49km/h.
MOVEMENT: Westward at 10 km/h
FORECAST: Global numerical deterministic and ensemble models are in agreement that INVEST 91W will move slowly westward and continue to develop over the next 12 to 24 hours (JTWC). According to NCHMF, In the next 48-60 hours, INVEST 91W continues to move in the West-Northwest direction, at about 10-15km and weakening. INVEST 91W may weaken into a Low-Pressure area (LPA) over southern Lao PDR.
The potential for the development of a significant tropical cyclone within the next 24 hours is HIGH
INVEST 92W
OVERVIEW: The area of convection INVEST 92W located near 17.1N 147.3E, approximately 495 km Northeast of Guam (JTWC).
INTENSITY: Surface winds are around 20-30 km/h (10-15 knots). Minimum sea-level pressure is near 1003 hPa.
FORECAST: Global numerical models agree that 92W will move westward and continue to develop over the next 2 days.
The potential for the development of a significant tropical cyclone within the next 24 hours is LOW
POTENTIAL IMPACTS
Cambodia:
- At most moderate to heavy rainfall over the Northeastern Highlands, Northern Highlands, and Northwestern Central Lowlands.
Lao PDR:
- At most moderate to heavy rainfall with thunderstorms over Phongsaly, SamNeua, Xieng Khouang, Oudomxay, Luang Namtha, Luang Prabang, Xayabouri, Vientiene, Phonhong, Pakxan, Thakhek, Pakse, Salavan, Sekong, and Attapeu.
Philippines:
- Strong Winds are expected over the southwestern sea area of the North East Sea (including the sea area of the Paracel Islands), and the northwestern sea area of the Central
- At most moderate to heavy rains and thunderstorms are expected over the Central Highlands, Western Highlands and Southern regions.
Thailand:
- At most heavy to very heavy rainfall over lower Northern, Northeastern, Central, Eastern, and Southern Regions in Thailand.
Viet Nam:
- Strong Winds are expected over the southwestern sea area of the North East Sea (including the sea area of the Paracel Islands), and the northwestern sea area of the Central
- At most moderate to heavy rains and thunderstorms are expected over the Central Highlands, Western Highlands and Southern regions.
IMPACTS AND DAMAGES
Philippines
- NDRRMC reported flooding and landslides since 16 September over Region VI, IX, XII, and BARMM.
- 84K families (402K persons) were affected, and around 5K persons were displaced.
- 2 persons dead, 1 person, and 1 injured.
- 17 houses (15 partially, 2 totally), 1 bridge, and 2 roads.
PREPAREDNESS AND RESPONSE
Cambodia
- MWRM Cambodia continue to monitor weather situation and provision of weather updates to all stakeholders.
Lao PDR
- DMH Lao PDR continue to monitor weather situation and provision of weather updates to all stakeholders.
Philippines
- As of 24 September, NDRRMC Alert Status is on Blue Alert (half of the members of the NDRRMC are on standby for any emergencies).
- A total of 3 cities/municipalities were declared under the State of Calamity in Maguindanao (BARMM).
- PAGASA continue to monitor weather situation and provision of weather updates to all stakeholders.
Thailand
- TMD continue to monitor weather situation and provision of weather updates to all stakeholders.
Viet Nam
- The National Steering Committee for Disaster Prevention and Control of Viet Nam has dispatch a letter No. 11/CD-QG dated 24 September 2023 to proactively response the potential impacts of Tropical Depression INVEST 91W (VDDMA).
- NCHMF continue to monitor 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.
