Mayon’s activity in the past 24 hours was characterized by sporadic and weak lava fountaining, lava flow and degassing from the summit crater. Although the upper slopes were heavily obscured, the seismic record indicated discrete episodes of lava fountaining that lasted five (5) to fifty (50) minutes. Throughout the night, lava flows and consequent incandescent rockfalls were observed in the Miisi and Bonga-Buyuan channels.  Effused volumes of incandescent lava flows have advanced to 3.3 kilometers, 4.5 kilometers and 900 meters down the Miisi, Bonga and Basud Gullies, respectively, from the summit crater. Pyroclastic density currents or PDCs have deposited to the 4.6, 4.5 and 4.2 kilometer reaches of the Miisi, Bonga and Basud Gullies, respectively. Heavy rainfall yesterday also generated channel-confined lahars in the Anoling channel and sediment-laden streamflows in channels where PDC deposits were emplaced.

A total of ninety-four (94) volcanic earthquakes, most of which corresponded to lava fountaining events were recorded by Mayon's seismic monitoring network. Electronic tilt and continuous GPS still record sustained swelling or inflation of the edifice since November and October 2017, consistent with pressurization by magmatic intrusion.

Alert Level 4 remains in effect over Mayon Volcano. The public is strongly advised to be vigilant and desist from entering the eight (8) kilometer-radius danger zone, and to be additionally vigilant against pyroclastic density currents, lahars and sediment-laden stream flows along channels draining the edifice. Civil aviation authorities must also 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.

DOST-PHIVOLCS