The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) issued an early morning advisory on Monday, January 5, 2026, warning the public that three distinct weather systems will bring damp conditions to a large portion of the archipelago.
Shear Line and Easterlies Trigger Scattered Rains
According to the state weather bureau's 4 a.m. bulletin, the shear line is expected to be the primary cause of scattered rain showers and isolated thunderstorms in several key areas. The affected regions include the entire Visayas, the Bicol Region, and the provinces of Quezon, Oriental Mindoro, Marinduque, and Romblon.
Simultaneously, the easterlies will influence weather patterns in the western part of the country. Residents in Zamboanga Peninsula, Basilan, Sulu, Tawi-Tawi, and Palawan should prepare for similar rainy conditions. PAGASA emphasized that in these areas, the moderate to heavy rainfall could lead to dangerous situations such as flash floods or landslides.
Amihan Brings Light Rains to Luzon
The northeast monsoon, locally known as "amihan," continues to affect Northern and Central Luzon. This weather system will bring light rains over the Cordillera Administrative Region, Cagayan Valley, Aurora, Laguna, Batangas, and the rest of the Mimaropa region. Metro Manila and the remaining parts of Luzon will experience isolated light rains.
For Mindanao, outside of the areas affected by the easterlies, the forecast calls for isolated rain showers or thunderstorms also due to the easterly winds.
Coastal Conditions and Cyclone Update
The weather disturbance will also impact sea conditions. Moderate to strong winds and moderate to rough coastal waters are forecast for the eastern section of the Philippines. For other parts of the country, winds will be lighter, ranging from light to moderate, with slight to moderate seas.
In a related development, PAGASA provided an update on potential storm formation. The bureau confirmed that it is not currently monitoring any low-pressure area that could develop into a tropical cyclone. This allows authorities and the public to focus on the immediate hazards posed by the ongoing rainfall and potential flooding.
Authorities advise residents in the warned areas to stay vigilant, monitor official updates, and take necessary precautions against possible flooding and landslides. The public is reminded to avoid unnecessary travel during heavy downpours and to heed evacuation orders from local disaster risk reduction management councils.
