Mayon Volcano is quietly pumping out sulfur dioxide at levels not seen in weeks, and PHIVOLCS says the rising gas could be a warning sign that the country's most active volcano is stirring again. The volcano in Albay is back under close watch after its summit crater vented high volumes of volcanic gas, even as its official alert level holds steady.
Why the gas numbers matter
PHIVOLCS recorded a surge in sulfur dioxide (SO2) emissions that scientists read as a possible shift toward renewed eruptive activity at the summit. Sulfur dioxide is one of the gases released by magma as it rises, so a spike is often one of the first measurable signs that a volcano is recharging.
- The spike: emissions reached as high as 7,115 tonnes per day on Aug. 31, the second-highest reading recorded since volcanic gas levels began easing on July 16.
- An earlier jump: an abrupt rise was also detected shortly after the alert was lowered, topping out near the highest SO2 volume logged in that stretch.
- The baseline: those elevated readings sit well above the thousands of tonnes Mayon has averaged each day since early August.
What PHIVOLCS is telling residents
The elevated gas output has been accompanied by a slight rise in low-frequency volcanic earthquakes tied to degassing, plus short-term swelling or pressurization detected on the volcano's northern and eastern flanks. Combined, these are the classic signals that magma may be moving back up toward the crater.
Entry into the six-kilometer Permanent Danger Zone remains prohibited. PHIVOLCS has reminded local governments and residents living around Mayon to prepare for a possible escalation, warning that a renewed eruption could send out pyroclastic density currents, rockfall, ballistic fragments, and widespread ashfall that would hit communities downwind.
Alert Level 2 stays, for now
Mayon has remained under Alert Level 2, or a moderate level of unrest, since it was lowered from Alert Level 3 on Aug. 5. That level means a hazardous eruption is not necessarily imminent, but the volcano is clearly restless and conditions can change quickly.
| Indicator | Current status (early Sept. 2026) |
|---|---|
| Alert level | Level 2 (moderate unrest) |
| Sulfur dioxide | Elevated, spiking to 7,115 t/day on Aug. 31 |
| Earthquakes | Slight rise in low-frequency events |
| Edifice | Short-term swelling on north, east flanks |
| Danger zone | 6-km Permanent Danger Zone closed |
What to watch next
Because elevated gas emissions could forewarn of renewed eruptive activity, the coming days will hinge on whether SO2 stays high, whether the swelling spreads, and whether quakes pick up. PHIVOLCS has advised communities to stay out of the danger zone and to monitor official advisories rather than rely on speculation.
Albay is no stranger to Mayon's moods. The region has prepared for and survived major eruptions before, and a survival guide for Mayon eruptions is worth a refresh for anyone living in its shadow. Just this past May, a meteor lit up the sky above Mayon, drawing fresh attention to the famous cone. And with the rainy season raising lahar risks at other volcanoes too, PHIVOLCS has issued lahar warnings for Pinatubo and Taal as the Habagat rains continue.
For now, the message from PHIVOLCS is simple: Mayon is under Level 2, the danger zone is off limits, and residents should stay alert and wait for official updates before assuming an eruption is on the way.
