PHIVOLCS reports multiple short-lived eruptions at Taal volcano

According to the Philippine Institute of Volcanology and Seismology (PHIVOLCS), four minor eruptive events occurred within a 24-hour period ending 17:00 LT (09:00 UTC) on October 26.

The sequence began at 17:31 LT on October 25, when a phreatomagmatic eruption at the northeastern sector of the Main Crater generated a dense, ash-laden plume that rose 1 200–2 100 m (3 900 – 6 900 feet) above the vent and drifted southwest.

At 02:55 LT on October 26, a short-lived phreatic explosion locally known as pusngat occurred, lasting about a minute and producing a billowing white plume above the Main Crater Lake. Two stronger phreatomagmatic eruptions followed at 08:13 and 08:20 LT, each lasting two to four minutes.

Infrasound sensors registered shock pressures up to 112 Pa at the Main Crater Observation Station (VTMC). Visual and thermal imaging confirmed dense plumes rising up to 2 100 m (6 900 feet) above the vent. Minor pyroclastic density currents descended slowly across the moat and inner walls of the Main Crater.

Rainfall in the area caused most of the ashfall to settle quickly over Barangays Banyaga (Agoncillo) and Buso-Buso, Gulod, Bugaan West and San Gregorio (Laurel), Batangas Province. Residents also reported transient sulfurous fumes.

Seismic data show that the sequence was preceded by nine volcanic earthquakes, including two hour-long tremor events, a frequency considered normal for Taal even during quiescent phases. No significant increase in RSAM (Real-time Seismic Amplitude Measurement) was detected prior to the explosions, suggesting a hydrothermal rather than a magmatic trigger.

Average sulfur dioxide emission measured 436 t/day on October 25, close to the short-term monthly average of 322 t/day and far below the long-term mean of about 4 847 t/day since 2021. Ground-deformation and microgravity data indicate localized swelling of Taal Volcano Island while the broader caldera continues to deflate, evidence that no new magma intrusion is occurring.

Waveform and spectral analysis of recent events show dominant frequencies near 1 Hz, typical of phreatomagmatic explosions at Taal. Infrasound data from five stations captured the onset and decay of the 08:20 LT eruption, confirming its short duration and low energy release.

PHIVOLCS reported no pronounced increase in volcanic earthquakes or ground deformation following the eruption sequence. As a result, Alert Level 1 remains in effect — low-level unrest associated with hydrothermal or gas-driven activity beneath the Main Crater.

The agency noted that similar short-lived phreatic or phreatomagmatic events may continue to occur without warning.

Residents and visitors are reminded that entry into Taal Volcano Island and the vicinity of the Main Crater and Daang Kastila fissure remains strictly prohibited due to the risk of steam-driven explosions, ballistic ejecta, and toxic gas emissions, while local governments continue monitoring possible ashfall and sulfur dioxide impacts in downwind communities. Civil aviation authorities also warn pilots to avoid flying close to the caldera due to potential ash and ballistic hazards.

Taal is located in southern Luzon within Taal Lake. It’s one of the most active volcanoes in the Philippines with a history of frequent hydrothermal and phreatomagmatic activity due to its shallow magma storage and water-saturated system.

Its January 2020 eruption caused widespread ashfall across Central Luzon and prompted large-scale evacuations. Since then, Taal has remained at low-level unrest with intermittent steam and gas bursts. The October 2025 eruption sequence is consistent with this pattern of shallow open-system degassing and surface water interaction rather than new magma movement.

Teo Blašković

I'm a dedicated researcher, journalist, and editor at The Watchers. With over 20 years of experience in the media industry, I specialize in hard science news, focusing on extreme weather, seismic and volcanic activity, space weather, and astronomy, including near-Earth objects and planetary defense strategies. You can reach me at teo /at/ watchers.news.

• Teo Blašković

  G3 – Strong Geomagnetic Storm Watch issued for June 4 and 5 following three significant solar flares
• Teo Blašković

  X1.0 solar flare erupts from geoeffective Region 4455
• Teo Blašković

  M9.3 and M7.7 solar flares erupt from AR 4455, launching Earth-directed CMEs
• Teo Blašković

  Kīlauea sets lava-fountaining record with episode 48, Hawaii