The northeast monsoon, or "amihan," is expected to strengthen this week, bringing cooler temperatures across Luzon, according to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA).

PAGASA Weather Specialist Veronica Torres said the cooler weather will extend as far as Calabarzon as the monsoon regains strength. In recent days, most of the country has experienced warm and humid conditions as the northeast monsoon weakened and only affected Extreme Northern Luzon.

"It may strengthen again around Thursday this week, and it can be felt in most parts of Luzon," Torres said in a phone interview.

As the northeast monsoon brings rain over Extreme Northern Luzon, Magat Dam in Isabela continues to release water due to inflows from recent rains. The Hydro-Meteorology Division - Flood Forecasting and Warning Section of PAGASA reported that one gate of Magat Dam remains open, though the discharge has decreased to 357.72 cubic meters per second, down from 488.06 cubic meters per second last Monday.

According to the PAGASA Flood Forecasting and Warning System for Dam Operation (PAGASA-FFWSDO), the water release may affect the towns of Alfonso Lista in Ifugao, Ramon, San Mateo, Aurora, Cabatuan, Luna, Reina Mercedes, Burgos, Naguilian, and Gamu. At least 5 to 20 millimeters of rain is expected over the Magat watershed in the next 24 hours.

Aside from the northeast monsoon, the country is also experiencing weather effects from the shear line, which is impacting the eastern seaboard of Northern Luzon, and the Intertropical Convergence Zone (ITCZ), which is affecting Mindanao. These weather systems are expected to bring localized rains in their respective areas in the coming days.