MAYON VOLCANO ADVISORY

11 July 2026

10:15 PM

 

This is a notice of increasing volcanic SO₂ emission from Mayon Volcano.

 

Increasing volcanic sulfur dioxide or SO₂ gas emission from the summit crater of Mayon Volcano, now on its 187th consecutive day of eruption, has reached very high concentrations today, 11 July 2026, based on measurements by campaign UV spectrometry. Volcanic SO₂ flux averaged 13,128 tonnes/day for the day, the highest emission from Mayon recorded in the last 26 years, only slightly lower than those measured during the explosive eruption of the volcano in 2000. This abrupt rise has been accompanied by an increase in the occurrence of low frequency volcanic earthquakes or LFVQs that are attributed to volcanic degassing and minor Strombolian activity at the crater, and increased rockfall linked to collapses from new lava flows.  As of 8:00 PM today, a total of 97 LFVQs and 304 rockfall events have been recorded by the Mayon Volcano Network. Only slight increases in swelling or inflation of the edifice, and slight increases in overall seismic energy release of the volcano, have been recorded so far, still consistent with the prevailing effusive activity that has characterized Mayon’s 2026 eruption to date. Nonetheless, elevated volcanic SO₂ emissions could forewarn of further or even a potential shift to explosive 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.

 

DOST-PHIVOLCS would like to remind the public that Mayon Volcano is at Alert Level 3 but that there are currently new possibilities that the behavior of ongoing eruption could change and even lead to explosive eruption. Such an eruption could generate more extensive and life-threatening volcanic hazards that include larger-volume and longer PDCs on all sectors of the volcano, rock fragments that can be thrown out as ballistic projectiles and more extensive ashfall that could severely impact communities downwind. The public must refrain from entering the 6-kilometer radius Permanent Danger Zone (PDZ) and communities and local government units within the pre-determined zones of PDC hazards must prepare and be ready to respond in case activity escalates and the alert level is stepped up to Alert Level 4. Increased vigilance and pre-emptive response actions to guard against lahars and sediment-laden streamflow along channels draining the edifice are also advised during sustained heavy or intense rains especially in the event of simultaneous explosive eruption. Civil aviation authorities should continue to advise pilots to avoid flying close to the volcano’s summit as ash and ballistic fragments from any sudden eruption can be hazardous to aircraft.

 

DOST-PHIVOLCS maintains close monitoring of Mayon Volcano and any new development will be communicated to all concerned stakeholders.

 

 

DOST-PHIVOLCS