Despite the rain showers and thunderstorms over the past few days, the Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA) on Wednesday, May 14 clarified that the official rainy season has not yet begun.

PAGASA weather specialist Benison Estareja explained that the rainy season will only be declared once the southwest monsoon (habagat) takes over as the dominant weather system, replacing the current easterlies, or warm winds from the Pacific Ocean.

“Hindi pa rin natin nakikita na mag-de-declare tayo ng pagsisimula ng tag-ulan o rainy season sa ating bansa dahil unang-unang criteria natin dapat ang hangin ay nanggagaling dito sa southwest instead of the easterlies (We do not yet see that we will declare the start of the rainy season in the country because, first and foremost, our criteria require the winds to come from the southwest, not the easterlies),” he said.

“Nakikita natin in the next four days, easterlies pa rin naman po ‘yung prevailing weather system sa ating bansa (In the next four days, we expect the easterlies to remain the prevailing weather system in the country),” he added.

The rainy season usually begins in the latter part of May or the first half of June.

Wet weekend

From Thursday to Sunday, May 15 to 18, Estareja said the Intertropical Convergence Zone (ITCZ) is expected to bring scattered rain showers, with occasional heavy rainfall to Palawan, Mindanao, and parts of the Visayas, including Cebu, Bohol, Siquijor, Negros Oriental, and Negros Occidental.

The ITCZ, where winds from the northern and southern hemispheres converge, can trigger flash floods and landslides in affected areas.

Meanwhile, Estareja said the rest of the country will experience partly cloudy to cloudy skies, with isolated afternoon or evening thunderstorms due to the easterlies.

He also confirmed that no tropical cyclones are expected to enter the Philippine Area of Responsibility until the end of the week.