The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) on Sunday, Dec. 15 said the shear line and northeast monsoon (amihan) may bring rains over parts of Luzon and Visayas in the next 24 hours, while a low-pressure area (LPA) may develop in the coming days.
PAGASA said the shear line, formed by the collision of cold winds of the amihan and the warm winds from the easterlies, will bring cloudy skies with scattered rains and isolated thunderstorms to Bicol Region and Northern Samar.
Cloudy skies with rains due to the amihan may also affect Cagayan Valley, Cordillera Administrative Region, Aurora, and Quezon.
PAGASA warned of flash floods or landslides in areas affected by the shear line and amihan, particularly during moderate to heavy rainfall.
The rest of the country will experience partly cloudy to cloudy skies with rain showers due to the amihan and easterlies.
PAGASA Weather Specialist Grace Castañeda also noted that an LPA may form from the cloud clusters east of Visayas and Mindanao in the next 24 to 48 hours.
Rains are possible in some parts of Visayas and Mindanao in the coming days due to the potential LPA or shear line, she added.