Pagasa declares onset of rainy season

MANILA, Philippines – It’s official: the rainy season is here.

Unlike in previous years, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) did not wait for its criteria to be met before announcing the onset of the wet season. 

“Yes, the rainy season is here,” Anthony Lucero, PAGASA assistant weather services chief, said in a press conference yesterday.

“We don’t need to finish all the observations before we announce it. We are doing this because we are estimating that in the next two to three days, there will be more rains,” he said.

Lucero also noted that the wind is now blowing from the southwest. 

PAGASA’s criteria in declaring the onset of the rainy season include the prevalence of the southwest monsoon and rainfall of 25 millimeters in at least five out of eight PAGASA stations for five consecutive days.

The PAGASA officials clarified that the onset of the rainy season applies only for areas under the Type 1 climate. These include the National Capital Region, Ilocos Norte, Ilocos Sur, Bulacan, Bataan, Pampanga, Zambales, Tarlac, Palawan, Mindoro, Cavite and Batangas. 

Esperanza Cayanan, PAGASA weather division chief, noted that rains in the past days have triggered flooding in several areas, including Metro Manila. 

“Before, we would wait for five days to meet the required 25 mm of rain, but because we have seen the impact of the rains in past few days, we decided to announce it in advance,” Cayanan said.

Excessive rain

Lucero also reiterated the possible development of a La Niña condition during the monsoon season.

“We are still under El Niño but we expect this will end at the end of July. From then, there will be a neutral condition. By the end of August, that is the time La Niña is expected to develop,” he said.

Lucero warned of possible landslide and flooding as La Niña is expected to bring above normal rainfall over the eastern section of the country by the last quarter of the year until early 2017. 

He said these areas include Isabela, Quirino, Quezon, Bicol region, Samar, Leyte, Surigao, Agusan, Compostela Valley and Davao Oriental.