Mayon Volcano’s seismic monitoring network recorded two (2) volcanic earthquakes and six (6) rockfall events during the past 24 hours. One (1) lava-collapse pyroclastic density current (PDC) event occurred on the Bonga-Buyuan Gully at 9:34 AM yesterday and generated dirty white ash clouds that drifted southwest.

Wispy to weak steam-laden plumes that drifted southwest were occasionally emitted from the summit crater throughout the day. At night time, faint crater glow could be observed, as well as intermittent incandescent rockfall from the unstable margins of lava flows on the Miisi, Bonga and Basud Gullies.

Sulfur dioxide (SO2) emission was measured at an average of 1062 tonnes/day on 26 March 2018. Slight inflation of the lower slopes that began on 11 March is still being recorded by electronic tiltmeter, consistent with results of Precise Leveling (PL) surveys on 10 - 19 March 2018. Overall ground deformation data indicate that the edifice is still swollen or inflated relative to pre-eruption baselines.

Alert Level 3 currently prevails over Mayon Volcano. This means that although Mayon’s unrest continues, there is a decreased likelihood of hazardous explosive eruption to occur. PHIVOLCS-DOST reminds the public of sudden explosions, lava collapses, pyroclastic density currents or PDCs and ashfall can still occur and threaten areas in the upper to middle slopes of Mayon. PHIVOLCS-DOST recommends that entry into the six kilometer-radius Permanent Danger Zone or PDZ and a precautionary seven kilometer-radius Extended Danger Zone or EDZ in the south-southwest to east-northeast sector, stretching from Anoling, Camalig to Sta. Misericordia, Sto. Domingo, must be strictly prohibited. People residing close to these danger areas are also advised to observe precautions associated with rockfalls, PDCs and ashfall. Active river channels and those perennially identified as lahar prone areas in the southern and eastern sectors should also be avoided especially during bad weather conditions or when there is heavy and prolonged rainfall. Civil aviation authorities must advise pilots to avoid flying close to the volcano’s summit as airborne ash and ballistic fragments from sudden explosions and PDCs may pose hazards to aircrafts. PHIVOLCS-DOST is closely monitoring Mayon Volcano’s activity and any new significant development will be immediately communicated to all stakeholders.