State volcanologists are urging residents living near rivers flowing from the Mayon volcano to be on alert due to the threat of lahar flows due to heavy rains caused by the shear line. 

Phivolcs Director Dr. Teresito Bacolcol said that while they have not yet monitored the presence of lahar due to heavy rains, it may still trigger lahar flows in the areas near the volcano. 

“Ngayon po, wala po tayong naiulat na lahar dulot ng shear line. Although hindi na masyadong maulan sa Legazpi ngayon, patuloy pa rin nating pinapayuhan ang ating mga residente lalo na ang mga nakatira malapit sa mga ilog na umaagos pa mula sa dalisdis ng Mayon na manatiling mapagmatyag. Lalo itong mahalaga kung magpapatuloy ang pag-ulan dahil maaaring magdulot po ito ng lahar [flow],” he said in a televised briefing. 

Shear line brings wet Christmas to Metro Manila, Southern Luzon

Areas identified to be at risk for lahar are those near the Miisi Channel, Binaan Channel, Anoling, Quirangay, Maninila, Masarawag, Muladbucad, Nasisi, Mabinit, Matan-ag, Bulawan, and Basud Channels, Bacolcol said.

 “So, basically iyong mga bayan na nasa southern, western and eastern sides of Mayon Volcano,” the official said.

 “So, agad silang lumikas patungo sa mga ligtas na lugar na itinakda ng lokal na pamahalaan; huwag na ngang tangkaing tumawid o lumapit pa sa mga ilog na posibleng daluyan ng lahar; and ang pinakaimportante ay makipag-ugnayan po sila sa mga local authorities para sa agarang tulong at impormasyon,” he continued.

Mayon Volcano remains under Alert Level 1, which means "a low level of unrest."

 No Christmas parties for Kanlaon evacuees as volcano threat remains

Meanwhile, the Phivolcs have monitored 20 volcanic earthquakes at the Kanlaon Volcano, which is currently under Alert Level 3.

 “And we were able to measure sulfur dioxide emission yesterday na umaabot ng 6,014 tons per day. These are all indications na again patuloy pa rin ang aktibidad ng bulkan and as I’ve mentioned nasa Alert Level 3 pa rin tayo,” he said.