The onset of northeast monsoon or “amihan” amid the re-emergence of the La Niña phenomenon will help improve the water supply potential of Angat Dam in Luzon.

Angat is Metro Manila’s main source of water.

Water in Angat is still below its normal high level but “amihan” can change that especially with La Niña’s help, Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) hydrologist Edgar dela Cruz said on Saturday.

“Rain from ‘amihan’ will raise Angat’s water and bring this closer to its normal high level,” he said.

The water rise will improve Angat’s capability to serve its customers in the coming months, he noted.

According to PAGASA, Angat Dam’s 6 a.m. water level on Saturday was at 199.67 meters. Such a level is already 10.33 meters lower than Angat’s 210 meters normal high.

“There’s hope for Angat as ‘amihan’ affects this dam more than the southwest monsoon or ‘habagat’ does,” dela Cruz said.

He said the watershed of Angat is located closer to the eastern section of Luzon so this dam generally receives more water from the rain of “amihan” than “habagat” which mainly affects the western section.

“Amihan” prevails in the country from around late October to early March, PAGASA weather forecaster Ana Clauren said

It is usually rainy in eastern sections of the country during “amihan” than in other areas nationwide, she noted.

She said La Niña may enhance “amihan” that may further increase rainfall.

On Oct. 15, PAGASA announced the termination of this year’s “habagat” season in the Philippines.

La Niña re-emerged this year so most areas of the country may experience near- to above-normal rainfall between October 2021 and the first quarter of 2022, PAGASA added.