The Philippine Institute of Volcanology and Seismology (PHIVOLCS) warned residents around Mayon Volcano to stay alert for possible lahar flows as #UwanPH brings heavy rains over the Bicol Region.

Based on PAGASA’s latest weather advisory, Uwan may bring intense to torrential rainfall of up to 400 millimeters from Friday to Saturday, which could trigger volcanic sediment flows or muddy floods in rivers and drainage areas on Mayon’s slopes.

PHIVOLCS urged local governments in Albay to prepare for possible evacuations, especially in areas identified as lahar-prone.

“Communities in pre-determined zones of lahar and related hazards must be ready and, if necessary, conduct pre-emptive evacuation,” the agency said.

It warned that rainwater could erode loose volcanic materials from Mayon’s previous eruptions in 2018 and 2023, triggering life-threatening lahars along the Miisi, Binaan, Mabinit, Buyuan, Anoling, Matanag, Bonga, and Basud Channels.

Older deposits on the volcano’s southwestern slopes may also be washed down through the Masarawag and Maninila Channels, posing threats to communities in Guinobatan. Other areas at risk include the Quirangay, Tumpa, Sua, Muladbucad, Nasisi, Nabonton, Buang, San Vicente, Bulawan, and Lidong Channels.

PHIVOLCS reminded residents and local officials to monitor rainfall continuously and take immediate safety measures.