The Department of Science and Technology-Philippine Institute of Volcanology and Seismology (DOST-PHIVOLCS) recorded 57 volcanic earthquakes at Mayon Volcano over the past 24 hours, according to its daily bulletin released on 25 May.
During the monitoring period, PHIVOLCS also observed three lava effusions with lava flows extending within four kilometers of the volcano. The lava flows affected the Basud, Bonga, and Mi-isi gullies, reaching 3.8 kilometers, 3.2 kilometers, and 1.8 kilometers, respectively. Episodic minor strombolian activity was also recorded.
The agency said volcanic activity included 14 volcanic tremors lasting between three and 80 minutes, 286 rockfall events, and eight pyroclastic density current signals. Of the 57 volcanic earthquakes detected, only 12 had sufficient records to determine their locations.
PHIVOLCS reported that the sulfur dioxide flux of Mayon averaged 1,124 tonnes per day during the latest observation period.
Moderate emission plumes reaching up to 300 meters above the crater were also observed drifting west and west-southwest.
PHIVOLCS continues to prohibit entry into the six-kilometer-radius Permanent Danger Zone and warned aircraft against flying close to the volcano.
The agency also reiterated warnings against hazards such as rockfalls, landslides, avalanches, ballistic fragments, lava flows, lava fountaining, pyroclastic density currents, moderate-sized explosions, and lahars during heavy and prolonged rainfall.
Alert Level 3 has remained hoisted over Mayon Volcano since 3 January 2026 due to what PHIVOLCS described as continued intensified magmatic unrest, prompting authorities to enforce strict restrictions in danger zones and prepare for possible evacuation if necessary.