Based on its Tropical Cyclone Advisory # 5 issued at 11:00 AM today (November 30, 2019), the Philippine Atmospheric Geophysical and Astronomical Services Administration (PAGASA) forecasts that the Bicol Region will be experiencing moderate to heavy rains and thunderstorms starting Monday (December 2, 2019) due to Typhoon “KAMMURI”.

In view of the above, DOST-PHIVOLCS strongly recommends vigilance and readiness of communities in pre-determined zones of lahar hazards in Mayon Volcano. Prolonged and heavy rainfall may generate post-eruption lahars on major channels draining the Mayon Volcano edifice from thick pyroclastic density current (PDC) material and ashfall deposited during the January-March 2018 Mayon eruption. The bulk of erodible PDC deposits occupy the watershed areas of the Miisi, Mabinit, Buyuan and Basud channels. These deposits can be remobilized by rainwater and incorporate existing erodible material on channel banks and channel beds to generate boulder-rich or sediment-rich lahars.

DOST-PHIVOLCS therefore warns of potential lahars and sediment-laden streamflows on all river channels draining the slopes of Mayon Volcano, particularly the Miisi, Mabinit, Matan-ag, Basud, Masarawag-Maninila and Quirangay Channels, that may be generated by heavy rainfall brought about by Typhoon “KAMMURI”. Communities and local government units beside these drainages are advised to be additionally vigilant and to move residents to high ground when heavy rains occur. Alert Level 2 remains in effect over Mayon Volcano. DOST-PHIVOLCS maintains its close monitoring and will communicate any new development to all concerned stakeholders.

DOST-PHIVOLCS