Mayon Volcano alert level raised to 2

MANILA, Philippines — State volcanologists raised Mayon Volcano’s alert status to Alert Level 2 early Thursday, January 1, citing a sharp increase in rockfalls and prolonged ground swelling that could signal magma moving beneath the volcano.

Phivolcs said in a 6 a.m. bulletin that it was elevating the alert from Level 1, or low-level unrest, to Level 2, which indicates increasing or moderate unrest driven by shallow magmatic processes.

The agency's monitoring instruments recorded 599 rockfall events in the last two months of 2025, averaging 10 events a day. Activity intensified in the final week of December, with rockfalls averaging 21 events daily. On December 31 alone, 47 rockfall events were logged — the highest number recorded in a single day over the past year. 

“Increased rockfall at Mayon has been a precursory sign of magmatic dome growth within the upper edifice preceding an eruption,” Phivolcs said, noting that similar conditions were observed before the volcano’s 2023 eruption.

Long-term swelling flagged

While the agency said there were no significant volcanic earthquakes or sulfur dioxide anomalies, it pointed to unusual ground deformation patterns that have persisted far longer than in previous unrest episodes.

Data from electronic distance measurement, continuous GPS, and electronic tilt monitoring show that Mayon’s eastern to northeastern slopes have been swelling since June 2024, or for nearly 18 months. Short-term inflation on the volcano’s western to southwestern slopes began in May 2025, according to Phivolcs.

The agency said the combination of persistent and increasing rockfall and both long- and short-term swelling could mean a higher chance of an eruption at the summit, potentially producing life-threatening hazards. 

With Alert Level 2 now in effect, Phivolcs warned of possible sudden explosions, pyroclastic density currents (locally known as uson), rockfalls, landslides and ballistic projectiles.

The public was reminded to strictly avoid the six-kilometer-radius Permanent Danger Zone, while local government units were urged to prepare communities within areas prone to pyroclastic density currents for possible evacuation if activity escalates further.

Phivolcs also advised civil aviation authorities to warn pilots against flying near the volcano’s summit, citing the danger posed by ash and ballistic fragments to aircraft.