LEGAZPI CITY — Sulfur dioxide emissions from Mayon Volcano surged to 8,165 tons, marking the second-highest daily level since volcanic gas concentrations began declining in mid-July, state volcanologists said Friday.

The Philippine Institute of Volcanology and Seismology (Phivolcs) warned that the sharp rise in gas emissions could signal a potential shift toward renewed eruptive activity at the summit crater.

Phivolcs cited that bad weather could compound the threat of volcanic hazards. A new eruptive phase could produce life-threatening pyroclastic density currents, rockfalls, ballistic material and heavy ashfall in downwind areas.

The high emission rate was calculated using stationary ultraviolet spectrometry measurements.

Since Mayon’s status was lowered to Alert Level 2 on 5 August, daily emissions had averaged 4,196 tons.

The sudden spike in volcanic gas coincided with four low-frequency volcanic earthquakes linked to degassing.

Real-time seismic energy release remains at background levels, but electronic tilt stations detected short-term swelling on the volcano’s northern and eastern slopes.

Mayon remains under Alert Level 2, indicating moderate unrest, but Phivolcs warned of possible recurring activity.

The agency reminded the public that entry into the six-kilometer Permanent Danger Zone remains strictly prohibited.

Local government units and residents in designated hazard zones were advised to prepare for potential evacuation if activity escalates and Alert Level 3 is declared.

Communities along river channels were also urged to take precautions against mudflows and lahars during heavy rains.