Increased volcanic sulfur dioxide observed from Mayon Volcano — PHIVOLCS

There is an increase in volcanic sulfur dioxide emissions but there is a decrease in rockfall and pyroclastic density current activities from Mayon Volcano, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported.

In a Mayon Volcano Advisory issued at 10:30 p.m. on Friday, the PHIVOLCS said that on the 186th consecutive day of Mayon Volcano's eruptive unrest it was also observed that there is a decrease in rockfall and pyroclastic density current or PDC (uson) activity, indicating a decline in the effusion of lava from the summit crater.

But the agency reported that "volcanic SO2 degassing measured by campaign spectrometry methods in the past two days have significantly increased."

"Volcanic SO2 flux yesterday averaged 4,569 tonnes/day and increased today, 10 July 2026, to 7,475 tonnes/day, the highest emission from Mayon recorded in the last 16 years. To compare, SO2 flux from the start of the eruption on 6 January 2026 until present averages 2,300 tonnes/day," PHIVOLCS said.

"Rising volcanic SO2 emissions likely forewarn of further eruptive activity at the summit crater and continued generation of volcanic hazards, the impacts of which can be worsened by the prevailing poor weather conditions over the volcano," the agency added.

Mayon Volcano remains under Alert Level 3, said PHIVOLCS, as "eruptive unrest and continued lava effusion persists based on current monitoring parameters."

With this, there will be volcanic hazards such as lava flows and collapse-fed rockfall and PDCs or uson on the southern and eastern slopes, ashfall that could be dispersed by strong winds.

The agency suggests the following actions:

• The public should refrain from entering the 6-kilometer radius Permanent Danger Zone (PDZ) due to the danger posed by these and other volcanic hazards.
• Increased vigilance and pre-emptive response actions to guard against lahars and sediment-laden streamflow along channels draining the edifice are also advised as prolonged heavy rains over Albay Province could occur with the passage of Typhoon “Inday” east of Luzon.
• Civil aviation authorities should continue to advise pilots to avoid flying close to the volcano’s summit as ash 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." — BAP, GMA News