MANILA – The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) is forecasting scattered to widespread rain showers across several parts of Luzon on Wednesday, December 11, 2025, driven by the combined effects of a shear line and the northeast monsoon (amihan). The weather disturbance poses risks of flash floods and landslides in low-lying and mountainous areas, with light to moderate rains expected to persist through the day.
The shear line—a convergence zone where cold amihan winds clash with warm air from the south—will trigger intermittent showers over the Cordillera Administrative Region (CAR), Ilocos Region, Cagayan Valley, and Aurora. Meanwhile, the amihan will enhance rainfall in the Ilocos Region, Zambales, Bataan, and Pampanga, bringing cloudy skies and isolated thunderstorms. “The shear line and northeast monsoon will continue to bring rainy conditions over these areas, so residents should remain vigilant,” PAGASA weather specialist Obet Badrina advised in the 5 a.m. bulletin.
Affected Areas and Forecast
- Heavy to Intense Rains (100-200 mm in 24 hours): Possible in CAR, Ilocos Region, and Cagayan Valley, heightening flood and landslide risks in vulnerable spots.
- Moderate Rains (50-100 mm): Expected in Aurora, Zambales, Bataan, and Pampanga.
- Scattered Showers: The rest of Luzon, with isolated thunderstorms in the afternoon.
Temperatures will range from 24°C to 31°C nationwide, with Metro Manila seeing highs of 29°C and lows of 25°C. No tropical cyclones are monitored, but the amihan could whip up moderate winds (20-40 kph) over northern Luzon, prompting advisories for small vessels to stay docked.
Risks and Safety Tips
PAGASA urged low-lying communities to monitor rising rivers and avoid crossing flooded areas, while mountainous zones should steer clear of steep slopes. “Even light rains can accumulate quickly—flash floods don’t announce themselves,” Badrina cautioned. The Department of Social Welfare and Development (DSWD) is on standby for relief, with preemptive evacuations in flood-prone Ilocos Norte and Cagayan.
As the holiday season ramps up with Simbang Gabi preparations, this midweek moisture serves as a gentle nudge: Pack the ponchos, stay updated via PAGASA apps, and let the rains rinse away worries—safely.
Weather Outlook Snapshot (December 11, 2025):
| Region/Area | Conditions | Rainfall (24 hrs) | Temp Range |
|---|---|---|---|
| CAR & Cagayan Valley | Cloudy, scattered showers | 50-200 mm | 23-30°C |
| Ilocos Region | Cloudy, intermittent rains | 50-150 mm | 24-31°C |
| Aurora, Zambales, Bataan | Partly cloudy, isolated thunderstorms | 25-100 mm | 25-32°C |
| Metro Manila | Partly cloudy, light rains | Trace-50 mm | 25-29°C |