MANILA, Philippines - The Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa) yesterday told Filipinos to prepare for the onset of the rainy season, which would start anytime next week.
Pagasa weather forecaster Nonoy About said the southwest monsoon is expected to set in next week based on the latest forecast. The southwest monsoon is the prevailing wind system during the rainy season.
“Based on real-time synoptic situation, the southwest monsoon will be in place during the third week of May,” About told The STAR in a phone interview.
“The rainy season will start without the intervention of any (weather) disturbance,” About said.
A 25-millimeter rainfall requirement and a southwest monsoon are some of the criteria used by Pagasa in determining the onset of the rainy season.
Meanwhile, About warned the public about the occurrence of tornadoes due to severe thunderstorms.
A strong tornado battered a village in Koronadal City in South Cotabato last Monday, destroying several houses.
“Tornadoes usually happen in areas where there are cumulonimbus clouds like the intertropical convergence zone,” About said.
He also said tropical cyclone “Emong,” which battered several provinces in Luzon last week, is the strongest typhoon to hit the Philippines during the summer season in the last two decades.
Emong, which weakened into a low-pressure area (LPA) over the weekend, was spotted yesterday at 680 kilometers northeast of extreme Northern Luzon and was expected to exit the Philippine area of responsibility yesterday.
He also explained that the three weather disturbances – Crising, Dante and Emong – did not trigger the onset of the rainy season because of the absence of a southwest monsoon.
“There is no southwest monsoon that would be enhanced by these weather disturbances,” About said. “The rains that we experienced in the past days were brought mainly by the weather disturbances.”
“That’s the reason why we are not declaring the onset of the rainy season despite the rains we experienced in the past several days,” About said.
He added Luzon would continue to experience good weather in the next five days except for thunderstorms in the afternoon or evening due to warm weather.
On the other hand, the Intertropical Convergence Zone will bring scattered rainshowers over the Visayas and Mindanao until the weekend.
No weather disturbance will affect the country this week.