Despite the inclement weather brought by Typhoon Aghon, the first tropical cyclone in the Philippines this year, the weather bureau PAGASA said that the onset of the rainy season has yet to begin.

"Based on our monitoring and assessment, [the rainy season] is not here yet," PAGASA weather specialist Joey Figuracion said in Tuesday's Quezon City Journalist Forum.

Figuracion further explained that rainy or wet seasons are only declared in the western parts of Luzon and Visayas.

"[We thought that] when the rainy season is declared, it is for the entire country, which is not true. This is only on the western side of Luzon and the western side of Visayas because this is where the pronounced high peak of rain occurs during this season," he explained.

"Right now, even though 'Aghon' entered the landmass, the rain recorded in the western side of Luzon is not that much," Figuracion added, saying that widespread rains usually happen in the occurrence of southwest monsoon, or Habagat, in the western side of Luzon.

"But at least, [there] are already rainshowers. So actually, we are on our way; we are already seeing a trend or indicator that this [rainy season] is near," he said.

Furthermore, the weather specialist said that there are criteria that PAGASA follows to declare the onset of the rainy season in the country, such as the presence of widespread rains.

"The rains in the stations we are basing them on need to continue, especially on the western side. Then, we are waiting for a southwesterly proponent wind, which also needs to continue. This must not fluctuate for three to six days," Figuracion said.

PAGASA earlier said that scattered rains experienced in the country in the past few weeks can be an indicator of the possible onset of the rainy season in June, bringing down the heat index in the country.

On Sunday, tropical depression Aghon intensified into a tropical storm over Tayabas Bay in southern Luzon.

As of this writing, no tropical cyclone wind signal has been hoisted.

It is expected to stay in the Philippine Area of Responsibility until Wednesday.