LEGAZPI CITY, Philippines , The Philippine Institute of Volcanology and Seismology (Phivolcs) issued a critical advisory on Monday, August 17, 2026. They are warning of potential renewed eruptive activity at Mayon Volcano. This warning comes after a significant surge in sulfur dioxide (SO2) emissions. The emissions reached a very high rate of 8,393 tons per day. This is the highest daily measurement recorded since July 16, 2026. Experts suggest this could signal a shift towards hazardous eruptions.
Mayon Volcano is located in the province of Albay in the Philippines. It is famous for its near-perfect cone shape. The volcano is one of the most active in the country.
Mayon Volcano’s Sulfur Dioxide Spike
On Monday, August 17, 2026, Mayon Volcano’s summit crater released an alarming amount of sulfur dioxide. The rate reached 8,393 tons per day. This is a dramatic increase from the average of 2,532 tons per day seen since August 5, 2026. Phivolcs noted that this abrupt rise follows a trend of swelling or pressurization. This swelling has been detected in the northern and eastern parts of the volcano’s structure.
Phivolcs stated that elevated SO2 emissions can indicate a potential shift to new eruptive activity. This activity could generate dangerous volcanic hazards. These include pyroclastic density currents (PDCs), also known as ‘uson’. Rockfalls and ballistic fragments can also be ejected from the crater. Extensive ashfall could impact downwind communities.
Current Alert Level and Warnings
Mayon Volcano remains under Alert Level 2. This signifies a moderate level of volcanic unrest. However, Phivolcs stressed that a new eruption phase could be life-threatening. The public is strongly advised to avoid the 6-kilometer radius Permanent Danger Zone (PDZ). Local government units and communities near potential hazard zones are urged to prepare for rapid response. This is in case the alert status is raised to Level 3.
Phivolcs also warned of increased vigilance against lahars and sediment-laden streamflows. This is especially important during sustained or heavy rainfall. Aviation authorities have also been advised to take necessary precautions.
Mayon Volcano’s Recent Activity
Mayon Volcano had been under Alert Level 3 since January 6, 2026. Its alert status was lowered to Alert Level 2 on August 5, 2026. This decision was based on a sustained decline in volcanic unrest observed since late July. Eruptive activity at the summit crater had steadily declined since peaking between July 11 and 18. Lava flows had stopped advancing, indicating a cessation of fresh magma supply. Volcanic earthquakes and seismic energy release also returned to pre-eruption levels. Sulfur dioxide emissions had also decreased after reaching a record average of 13,128 tons per day on July 11, 2026.
However, monitoring data still indicated that magma remains stored beneath the volcano. Ground deformation and gravity measurements showed the edifice was still pressurized.
Context and Previous Events
Mayon Volcano is known for its frequent and sometimes dramatic eruptions. In January 2026, authorities evacuated nearly 1,000 families as the volcano oozed lava. Alert Level 3 was raised after observing the “onset of dome collapse pyroclastic density current”. This indicated a magmatic eruption with an increased likelihood of lava flows and hazardous PDCs.
More recently, on August 2, 2026, Mayon emitted ash from its summit crater. This event lasted about a minute, producing a grayish plume that rose 200 meters above the crater. The effusive eruption had continued for 208 consecutive days at that time, with Alert Level 3 in effect.
Reactions and Expert Commentary
Local governments have been advised to prepare for a possible escalation of volcanic activity. They are to be ready for a potential return to Alert Level 3. The head of the Albay Public Safety and Emergency Management Office (Apsemo) had previously emphasized the need for continued vigilance.
“Elevated volcanic SO2 emissions could forewarn of a potential shift to renewed eruptive activity at the summit crater that could generate volcanic hazards all around the volcano, the impacts of which can be worsened by the prevailing poor weather conditions,” Phivolcs stated.
What’s Next
The situation at Mayon Volcano is being closely monitored. Phivolcs continues to assess the data for any further changes in volcanic unrest. Residents in nearby communities are urged to remain vigilant and follow the guidance of local authorities. Further updates will be provided as the situation develops. More information will be available from Phivolcs as monitoring continues.
