Bulusan Volcano in Sorsogon erupted early Monday morning, April 28, at 4:36 a.m., prompting the Philippine Institute of Volcanology and Seismology (Phivolcs) to raise the volcano’s status from Alert Level 0 to Alert Level 1.
According to Phivolcs, the eruption was phreatic, producing a bent plume that rose 4,500 meters above the crater before drifting west to southwest. The event lasted for about 24 minutes.
Phivolcs explained that raising the alert level means the volcano is currently exhibiting "low-level unrest," with the possibility of further steam-driven or phreatic eruptions.
Ashfall was reported in several areas, including the barangays of Cogon and Bolos in Irosin, as well as Puting Sapa, Guruyan, Buraburan, and Tulatula Sur in Juban.
Phivolcs also noted that within three kilometers of the summit vent, a pyroclastic density current (PDC), locally known as "uson," flowed down the volcano’s southwest slopes.
Local officials reported hearing "rumbling sounds" about 15 minutes before the eruption, which were captured by infrasound sensors.
Due to the risk of volcanic hazards such as ashfall, pyroclastic flows, ballistic projectiles, rockfalls, and lahars, authorities warned the public to strictly avoid the four-kilometer Permanent Danger Zone (PDZ) and to stay vigilant within the two-kilometer Extended Danger Zone (EDZ) on the southeast sector.
Communities affected by ashfall are advised to take precautionary measures, including wearing masks or using wet cloths to prevent inhalation.
Pilots are likewise advised to avoid flying close to the volcano’s summit due to the danger posed by airborne ash, which can damage aircraft.
Meanwhile, Phivolcs recorded 53 volcanic earthquakes within the 24-hour period prior to the eruption.
