MANILA, Philippines - The heavy rain to be spawned by approaching Tropical Storm "Mario" may cause lahar flows along the slopes of the restive Mayon Volcano, the state weather bureau warned on Thursday.
In a televised press briefing before Thursday noon, the Philippine Atmospheric, Geophysical and Astronomical Services warned that the rain to be brought by the storm may dislodge lahar deposits.
"Itong mga pag-ulan niya, pinapangambahan natin ay pwedeng magpadausdos ng mga lahar na nakadeposit pa rin dito sa tabi ng Mayon Volcano," said Landrico Dalida, Jr. PAGASA deputy administrator of operations.
He also warned that heavy rains may also trigger landslides at the foot of the volcano.
"Mario" was estimated at 477 kilometers east of Virac, Catanduanes at 10 a.m. today.
According to PAGASA, Mario and the southwest monsoon or habagat will bring moderate to heavy rains and thunderstorms in the Bicol region where Mayon Volcano is located.
In the press briefing, PAGASA senior weather forecaster Rene Paciente said moderate to heavy rainfall is expected tonight in the Bicol area.
Earlier, the agency said in a special weather forecast that the Mayon area will have cloudy skies with rainshowers or thunderstorms until 10 a.m. tomorrow.
The Philippine Institute of Volcanology and Seismology (Phivolcs) has placed the volcano on alert level 3 due to its increased restiveness.
This means that magma is at the crater and that hazardous eruption is possible within weeks.
Phivolcs said Mayon Volcano's seismic network recorded 142 volcanic earthquakes and 251 rockfall events in a 24-hour period.
It also observed moderate emission of white steam plumes from the volcano that drifted south southwest was observed. Rain clouds covered the summit preventing visual observation.
About 4,742 families or 21,092 people have fled to 18 evacuation centers.