A. Situation analysis
Description of the disaster
7 November 2020: Low pressure area in the east of Mindanao has developed into a Tropical Depression Ulysses.
9 November 2020: Tropical Depression Ulysses strengthened from a tropical depression into a tropical storm – which now internationally known as Tropical Storm Vamco.
11 November 2020: Typhoon Vamco made its first landfall in the vicinity of Patnanungan, Quezon at 10:30 pm local time, second landfall in the vicinity of Burdeos, Quezon at 11:20 pm on the same day and third landfall in the vicinity of General Nakar, Quezon at 1:30 am on 12 November 2020.
According to Philippines Atmospheric, Geophysical and Astronomical Services Administration (PAGASA)
Typhoon Vamco (locally known as Ulysses) with maximum sustained winds of 155 kilometers per hour and gusts of up to 255 kilometers per hour, moving west-northwest at 20 kilometers per hour. The typhoon made its first landfall in Patnanungan, Quezon south of the capital Manila at 10:30 pm local time, while the second landfall was in Burdeos,
Quezon at 11:20 pm. Typhoon Vamco made its third landfall in General Nakar, Quezon at 1:30 am.
The typhoon slightly weakened while crossing Central Luzon in part due to the presence of the Sierra Madre and Zambales Mountain Ranges. Typhoon Vamco will continue crossing the landmass of Central Luzon. On the forecast track, the typhoon may exit the Philippine Area of Responsibility (PAR) on Friday morning or afternoon.
Throughout the passage of the typhoon, destructive typhoon-force winds were experienced in areas under Tropical Cyclone Wind Signal (TCWS) #3, damaging gale to storm-force winds in areas under TCWS #2, and strong breeze to near gale conditions in areas under TCWS #1.
Destructive winds and heavy to intense rainfall have been experienced over central and southern portions of Aurora, the northern portion of Quezon including Polillo Islands, Nueva Ecija, Bulacan, Tarlac, Pampanga, Pangasinan, Zambales, Bataan, Metro Manila, and Rizal.
PAGASA issued flood advisories for river basins in Pampanga, Cagayan, and Bicol region ahead of the anticipated landfall of the Typhoon Vamco. Flood advisory was issued for the Pampanga River Basin due to the slow to gradual rise of the upper main Pampanga River and its eastern major tributaries — Coronel, Digmala, Santor, Penaranda and Angat rivers. PAGASA warned of possible rain induced landslides and flash floods at the western slopes of Sierra Madre mountains particularly in the eastern part of Nueva Ecija, eastern part of Bulacan, and Pampanga-Tarlac area.
Typhoon Vamco is the Philippines' 21st tropical cyclone for 2020. Still suffering from Super Typhoon Goni, Bicol was the first to face Typhoon Vamco's winds and rain, as the typhoon triggered floods in parts of the region. The island province of Catanduanes and provinces of Albay, Camarines Norte and Camarines Sur, that bore the brunt of Typhoon Goni in late October, a Category 5 typhoon that killed 25 people and left six people missing were also affected by strong winds and rain.
However, the main impact of the typhoon was to Metro Manila and its adjacent provinces. The densely populated capital region of Metro Manila, though not directly hit by the center of the typhoon, is also affected with floods, fallen trees and power cables down leading to power outages across different cities. Nearby dams are closed to spilling, which could aggravate flooding. Airline flights and mass transit in the capital were suspended while the coast guard stopped port operations. Government work was suspended, and financial markets were shut. Hundreds of residents were forced to flee their homes on Thursday as water in Marikina River surpassed the peak level during the onslaught of Typhoon Vamco.
The typhoon is seen to continue bringing torrential rains to Metro Manila and other parts of Luzon until Thursday afternoon. Thursday morning the water level rose to 21.7 meters — higher than the 21.5 meters reached when Ondoy that caused significant disruption to the country 11 years ago and left Marikina City submerged in floodwater for days. Residents near the river were forced to evacuate when the water rose to 18 meters due to nonstop rains. The local government is also deploying rescue boats to extricate stranded residents.
Residents in low-lying areas near the Angat, Caliraya, La Mesa, and Ipo dams have been warned by state weather bureau PAGASA for possible flooding due to its water release triggered by heavy rainfall from Typhoon Vamco. Angat Dam's reservoir water level is in critical range as of Thursday morning. Authorities said the dam will open its spillway gates with initial gate opening of 0.5 meters at 10.00 am to ensure its stability. The authorities are warning nearby residents that water in Angat River is expected to rise due to the opening of gates and have been alerted to watch out for possible floods. As of 11 November 2020, the Office of Civil Defense in the Bicol Region has recorded one death, while three others missing, and more than 170,000 displaced in Bicol due to Typhoon Vamco.
According to report released by AHA Centre on 11 November 2020, an estimated 19.1 million people, 3.61 million households, and 126 billion US dollars of infrastructure are potentially exposed to moderate to severe damaging winds.