FLASH UPDATE #1 – Tropical Cyclone GENER (INVEST 98W)
Countries under monitoring: Lao PDR, Philippines, Thailand, Viet Nam
OVERVIEW: According to PAGASA, the low pressure area east of Aurora has developed into Tropical Depression GENER. At 1500H UTC+7, the centre of Tropical Depression GENER was estimated based on all available data at 290 km East of Tuguegarao City. JTWC previously identified this system as a monsoon depression and has now identified this as INVEST 98W with medium potential for development into a significant TC in the next 24 hrs. Meanwhile, PAGASA has already raised Tropical Cyclone Wind Signals (TCWS) in Luzon as TC GENER is expected to make landfall tonight or tomorrow early morning, and further enhance the southwest monsoon. In addition, PAGASA is also closely monitoring Tropical Cyclone “PULASAN” which has developed approximately 1,945 km east of Southeastern Luzon, currently outside of the Philippine Area of Responsibility and has a forecast track similar to TC BEBINCA.
STRENGTH & MOVEMENT: According to PAGASA’s Tropical Cyclone Bulletin No. 4, 16 September at 1600H UTC+7:
- Maximum sustained winds of 55 km/h near the center, gustiness of up to 70 km/h, and central pressure of 996 hPa, moving northwestward at 10 km/h.
FORECAST: According to Philippines’ PAGASA Tropical Cyclone Bulletin 4:
- TRACK: GENER is forecast to make landfall in the vicinity of Isabela or Aurora tonight or tomorrow early morning and may likely emerge over the coastal waters of La Union or Pangasinan tomorrow (17 September) late morning or noon. The tropical cyclone will then move generally westward over the West Philippine Sea until Wednesday (18 September) before turning northwestward on Thursday (19 September) as it heads towards southern mainland China. GENER may exit the Philippine Area of Responsibility (PAR) between tomorrow late evening and Wednesday morning.
- INTENSITY: GENER will likely cross the landmass of mainland Luzon as a tropical depression, although the possibility of reaching tropical storm category or slight weakening prior to landfall is not ruled out. Over the West Philippine Sea, GENER may reach tropical storm category tomorrow evening or on Wednesday morning.
HAZARDS:
- TCWS : Tropical Cyclone Wind Signal 1 (Warning lead time: 36 hrs; range of wind speeds: 39 to 61 km/h (Beaufort 6 to 7) is raised over the following areas:
- Luzon: Cagayan including Babuyan Islands, Isabela, Quirino, Nueva Vizcaya, Apayao, Kalinga, Abra, Ifugao, Mountain Province, Benguet, Ilocos Norte, Ilocos Sur, La Union, Pangasinan, Zambales, Tarlac, Nueva Ecija, Aurora, and the northern portion of Quezon (General Nakar, Infanta, Real), including Polillo Islands.
- Heavy Rainfall – According to PAGASA Weather Advisory No. 20 issued at 1300H UTC+7, moderate to intense rainfall are expected due to the Southwest Monsoon and TC GENER in the following areas :
- 16 September afternoon to 17 September afternoon : Heavy to intense rainfall in Palawan, Occidental Mindoro, Aklan, Antique, and Negros Occidental, Cagayan, Isabela, Quirino, and Aurora; Moderate to heavy in the rest of MIMAROPA, the rest of Western Visayas, Negros Island Region (NIR), Bicol Region, Cordillera Administrative Region, the rest of Cagayan Valley, Ilocos Norte, Nueva Ecija, and Bulacan
- 17 September afternoon to 18 September afternoon : Heavy to intense rainfall in Palawan, Occidental Mindoro, Aklan, and Antique, Negros Occidental, Cagayan, Isabela, Apayao, Mt. Province, Kalinga, Ifugao, Aurora, and Polilio Islands; moderate to heavy in Metro Manila, CALABARZON, the rest of MIMAROPA, the rest of Western Visayas, the rest of Negros Island Region, Bicol Region, Central Visayas, Ilocos Region, the rest of Cagayan Valley, the rest of CAR, and the rest of Central Luzon
- 18 September afternoon to 19 September afternoon: Heavy to intense rainfall in Occidental Mindoro; moderate to heavy in Metro Manila, Zambales, Bataan, Aklan, Antique, the rest of MIMAROPA, Cagayan including Babuyan Islands, Isabela, and Apayao
- Severe Winds – Minimal to minor impacts from strong winds are possible within any of the areas under TCWS Signal No. 1.
- The Southwest Monsoon enhanced by GENER and “PULASAN” will also bring strong to gale-force gusts over the following areas (especially in coastal and upland areas exposed to winds)
- Today: Batanes, MIMAROPA, Bicol Region, Visayas, Zamboanga Peninsula, Northern Mindanao, Caraga Region, and Davao Region
- Tomorrow (17 September): Batanes, MIMAROPA, Bicol Region, Visayas, and Mindanao
- Wednesday (18 September): Zambales, Bataan, Pampanga, Bulacan, Metro Manila, CALABARZON, MIMAROPA, Bicol Region, Visayas, and Mindanao
- Under these conditions, flooding and rain-induced landslides are likely, especially in areas that are highly or very highly susceptible to these hazards as identified in hazard maps and in areas with significant antecedent rainfall.
- Flood advisories are already raised in Luzon and Visayas due to heavy rainfall brought by the Southwest Monsoon.
- NDRRMC and the PHIVOLCS are also currently monitoring heightened activity of Mt. Kanlaon; Muddy flows have been observed on 14 Sept in the cities around Mt. Kanlaon, persistent heavy rainfall in the area could trigger lahar flows. As of 15 Sept, DSWD reports that about 57K persons were affected by the activity of Mt Kanlaon that started in June and of these, 2.45K persons remains displaced and are being served in 9 evacuation centres.
PREPAREDNESS AND RESPONSE:
- PAGASA advises the public and disaster risk reduction and management offices concerned to take all necessary measures to protect life and property. Persons living in areas identified to be highly or very highly susceptible to these hazards are advised to follow evacuation and other instructions from local officials.
- PAGASA issues localised heavy rainfall warnings, thunderstorm/rainfall advisories, and other severe weather information products issued through PAGASA Regional Services Division.
- DENR-MGB has released list of areas susceptible to rain-induced landslides along the areas with heavy rainfall outlook.
- PAGASA continues to monitor and release advisories and early warning information about these weather disturbances.
The AHA Centre will continue to monitor for further developments and issue necessary updates.
DATA SOURCES
ASEAN Disaster Monitoring & Response System (DMRS), ASEAN Disaster Information Network (ADINet); Pacific Disaster Center (PDC Global); ASEAN Specialised Meteorological Centre (ASMC);
Philippines: NDRRMC, PAGASA, PHIVOLCS, DSWD;
Verified news media agencies;
