Mount Bulusan (Image sourced from the Sorsogon Public Information Office / Facebook / Phivolcs)
LEGAZPI CITY — The Philippine Institute of Seismology and Volcanology (Phivolcs) on Monday said rain-triggered lahar flow occurred on the southwestern slopes of Mount Bulusan in Irosin, Sorsogon.
In an advisory issued at 1 a.m., Phivolcs said a small-volume lahar that began at 7:04 p.m. on Sunday was detected by seismic and infrasound stations of the Bulusan Volcano Network along Calang Creek in Barangay Cogon.
The event lasted 54 minutes during a period of thunderstorm in the province, Phivolcs said.
On Sunday night, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa) in Southern Luzon issued a thunderstorm advisory in six provinces of the Bicol region.
Pagasa said moderate to heavy rain with lightning and strong winds were experienced in the region.
Phivolcs recorded phreatic eruptions on June 5 and June 12 that covered several villages in Sorsogon with ash.
The agency warned local officials and residents near the channels of another lahar and sediment-laden stream flows that could be triggered by heavy rainfall.
The volcano is still inflated and remains under Alert Level 1.