The trough of a low pressure area (LPA) outside the Philippine area of responsibility (PAR) is extending and affecting the eastern sections of Luzon and Visayas, according to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA).
In the 5 a.m. weather bulletin issued on Saturday, PAGASA weather specialist Benison Estareja said the LPA was spotted at 2,150 kilometers east of Batanes.
“It may develop into a tropical cyclone within 48 to 72 hours, and we are not discounting the possibility that this will enter the PAR,” he said.
However, its chance of making landfall over the Philippines is slim as the LPA was already at a high latitude when it formed, Estareja explained.
“It can either move towards Japan or Taiwan so we will closely monitor this weather disturbance. It does not have a direct effect yet but expect the trough or extension to affect eastern Luzon and Visayas,” he added.
Scattered rain showers and thunderstorms are already affecting Albay, Camarines Norte, Camarines Sur, Catanduanes, Sorsogon, Masbate, Nueva Ecija, Aurora, and Quezon on Saturday.
Estareja said the southwest monsoon or “habagat” although weak still prevails over Western Visayas, Oriental Mindoro, Occidental Mindoro, Marinduque, Romblon, and Palawan.
Palawan may experience scattered rain showers and thunderstorms.
Warm weather from morning till noon may prevail over Metro Manila and the rest of the country.
However, short-lived rain showers due to localized thunderstorms may affect these areas in the afternoon until evening, that sometimes may extend until early morning, Estareja said.
Due to the possibility of heavy rain showers during severe thunderstorms, PAGASA advised the public to take necessary precautionary measures in case of flooding or landslides.
Based on the PAGASA’s historical climate data, an average of two to three tropical cyclones usually enter or form within the PAR in October.
With a full-blown La Niña that will affect the country in the coming months, the chances of having landfalling or crossing tropical cyclones are higher, and most of the country may experience near to above normal rainfall during this period.
“This October, there is a high chance that tropical cyclones will make landfall in Luzon and the northern part of Visayas, when the cyclone enters the PAR at a lower latitude,” Estareja explained.
“Other tropical cyclones have a slim chance of making landfall if it enters the PAR at a higher latitutde, if ever, it recurves towards Japan or Northern Pacific Ocean,” he added.
He also noted that the above normal rainfall that the country could receive will possibly come from the northeast monsoon or “amihan,” tail-end of cold front, or tropical cyclone.
PAGASA’s rainfall forecast this month shows that the Cordillera Administrative Region, Ilocos Region, Cagayan Valley, most parts of Visayas and Mindanao may receive near normal rainfall, while major portions of Central and Southern Luzon, Bicol Region, and Metro Manila may have above the normal amount of rainfall during this period.