Floods back, but it’s not yet rainy season – Pagasa

‘HEAVY AND INTENSE RAIN SHOWER’ Thunderstorm cells merged and brought “heavy and intense rain shower” that caused flooding in Metro Manila and parts of Rizal province on Wednesday night, according to the weather service.

The rainy season is not here yet, the state weather bureau said on Thursday, despite the heavy rainfall that flooded roads and caused gridlock in Metro Manila the night before.

But it’s best to always be ready with umbrellas as localized thunderstorms are expected to bring rains during late afternoons through evenings for the rest of the month, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa) said.

Begins in June

According to the bureau’s climate outlook released in April, the rainy season will officially begin around June.

Ailene Abelardo, a hydrologist with Pagasa, said Wednesday’s heavy rainfall was caused by thunderstorm cells that merged and brought rains to Metro Manila and parts of Rizal province.

A thunderstorm advisory issued at 7 p.m. on Wednesday warned of “heavy and intense rain shower” in those areas, including parts of central and southern Luzon, such as Laguna, Quezon, Bulacan, Pampanga and Cavite provinces.

Abelardo said the heaviest downpour that day was recorded between 5 p.m. and 8 p.m.

At the Pagasa Science Garden in Quezon City, at least 49 millimeters of rainfall was measured in just three hours.

The weather disturbance, however, did not help to refill the dams, particularly Angat and La Mesa, where the water levels had been dipping as the summer heat persisted.

Water in Angat Dam, located in Norzagaray, Bulacan province, even fell further by 0.36 meters, with its elevation recorded at 174.78 m on Thursday morning.

The water level of La Mesa Dam in Quezon City increased by 0.10 m, marking 68.55 m on Thursday morning.

Dams not refilled

Both dams remained way below their normal high water levels.

Abelardo said it was possible the rain did not fall exactly in the dams’ watersheds, so it did not greatly improve water depth.

In its 4 p.m. weather bulletin on Thursday, Pagasa said the country would continue to experience cloudy skies.

The intertropical convergence zone will bring scattered rain showers and thunderstorms in the Visayas, Northern Mindanao, Bicol and Mimaropa, while localized thunderstorms will bring isolated rainfall in Metro Manila and the rest of the country.

The low pressure area being monitored near Mindanao had entered the Philippine area of responsibility as of 8 a.m. Thursday. It was spotted 925 kilometers east of Hinatuan, Surigao del Sur province, in the afternoon.

It was unlikely to become a tropical storm, said weather specialist Gener Quitlong, citing available data.

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