Bulusan Right Now: Restless at Alert Level 1
Bulusan has been under Alert Level 1— "low-level unrest with increased chances of phreatic eruptions" — since PHIVOLCS raised it on March 22, 2026, and it remained there through early November (ASEAN AHA Centre Weekly Disaster Update, Nov 2–8, 2026). The unrest has been real: PHIVOLCS logged a swarm of 442 volcano-tectonic earthquakes in a single May 2026 bulletin (with 55 within 5 km of the vent), alongside ground swelling on the northern slopes detected since mid-2025. Sulfur dioxide output has stayed low — 121 tonnes per day on April 22.Sources: ASEAN AHA Centre Weekly Disaster Update (Nov 2–8, 2026); PHIVOLCS-DOST via GMA News (Alert Level 1 raised March 22, 2026; 442-earthquake bulletin, May 20, 2026); Philippine Information Agency (steam-driven blast warning). Checked November 13, 2026.
What PHIVOLCS keeps flagging is not a lava flow but a suddensteam blast. The agency warns the current unrest could trigger phreatic eruptions "at any of its summit vents" — producing ash columns, ballistic rock fragments, and, after heavy rain, lahars down the river channels. That is why the 4-kilometer Permanent Danger Zone stays strictly closed and a 2-kilometer Extended Danger Zone on the southeast flank is under watch, even at the lowest non-zero alert level. If you want the global picture of which volcanoes are elevated this week, our live eruption tracker pulls the same feeds.
Live status (as of November 13, 2026)
Alert level: 1 of 5 (low-level unrest, phreatic eruptions possible). Danger zones: 4 km Permanent Danger Zone (no entry), plus a 2 km Extended Danger Zone on the SE sector. Main hazards: sudden ash blasts, ballistic ejecta, lahars after rain. Confirm the current reading on PHIVOLCS before you travel or decide to stay.
Erupts Often, Never Big: Bulusan's Fingerprint
Here is the number that reframes everything about Bulusan. Across our Smithsonian GVP record (volcano id 528), Bulusan has 26 recorded eruptions. Of the 21 that carry a size rating, 18 are VEI-2, just two reached VEI-3 (the 1979–80 and 1981 episodes), and one was a VEI-1. It has never exceeded VEI-3. For comparison, neighboring Mayon has twice reached VEI-4 and Krakatau once hit VEI-6 — Bulusan is in a different, much smaller weight class.
It makes up for size with frequency. Bulusan has had nine separate eruptive episodes since the year 2000— in 2006 (twice), 2010, 2015, 2016 (twice), 2017, 2022, and 2025 — which ranks it among the busiest of the Philippines' two dozen volcanoes with historical eruptions. Almost every one of those was phreatic: steam, ash, and rock, with no lava. The table below is drawn straight from our database.
| Period | VEI | Character | What happened |
|---|---|---|---|
| 2025 | — | Confirmed eruption (phreatic) | The most recent confirmed activity on record. Short-lived steam-and-ash explosions, the pattern Bulusan has repeated for well over a century. |
| 2022 | 2 | Phreatic ash explosions | A sudden June 5, 2022 phreatic eruption threw up ash with almost no precursor, dusting Sorsogon towns — a textbook example of why PHIVOLCS treats Bulusan's quiet as deceptive. |
| 2015–2017 | 1–2 | Multi-year phreatic episode | A long run of intermittent steam-driven blasts from the summit and SE-flank vents. Three separate catalogue entries (2015, 2016 ×2, 2017) covering dozens of small explosions. |
| 2010–2011 | 2 | Phreatic episode | Repeated ash explosions from the summit crater through 2010 into 2011, again without magmatic lava reaching the surface. |
| 1978–1983 | 2–3 | The largest modern episode | Bulusan's two biggest eruptions on record — VEI-3 events in 1979–80 and 1981 — bracketed by VEI-2 activity. This is as large as Bulusan has ever gotten in the catalogue. |
Summary of a 26-eruption record (18× VEI-2, 2× VEI-3, 1× VEI-1, the rest unrated). Source: Smithsonian GVP (id 528), verified from our database Nov 13, 2026. See every dated eruption on our Bulusan database page.
Why a Volcano This Small Still Empties the Danger Zone
If Bulusan has never gone beyond VEI-3, why does PHIVOLCS clear a 4-kilometer radius for it? Because the hazard that kills at Bulusan is not magnitude — it is timing. Most of its eruptions are phreatic: shallow groundwater flashes to steam against hot rock and blows existing ash and boulders out of the vent, with no fresh magma needed. A magmatic eruption usually announces itself for days or weeks as magma forces its way up, tilting the ground and setting off earthquakes. A phreatic blast can skip almost all of that. On June 5, 2022, Bulusan erupted with essentially no immediate warning, throwing ash over nearby Sorsogon towns.
The near-vent dangers in that scenario are real even from a "small" eruption: ashfall that fouls lungs, water and crops; ballistic rocks hurled from the crater; and, because Bulusan's slopes feed several rivers, lahars — concrete-like volcanic mudflows — whenever heavy Bicol rain remobilizes fresh ash. True pyroclastic flows are possible in its larger episodes but rare. Knowing which hazard is coming changes what you should do — which is the whole point of our volcano safety guide.
Bulusan vs the Philippines' Other Restless Volcanoes
The Philippines has 24 volcanoes with historical eruptions, and the ones making news right now behave very differently. Bulusan's frequent, small, steam-driven blasts are a world apart from Mayon's dome-fed magmatic eruptions or Taal's caldera. Each card links to its full eruption history in our database.
26 eruptions · max VEI-3
This page. Sorsogon. Erupts often and small — mostly steam-driven blasts with little warning.
69 eruptions · 2× VEI-4
Albay. The opposite danger: magmatic, dome-fed eruptions that shed pyroclastic flows. At Level 3 and building in Nov 2026.
caldera · phreatomagmatic
Batangas. A lake-filled caldera whose 2020 eruption was driven by magma meeting water — a different, often deadlier mechanism.
ongoing since 2024
Negros. In a drawn-out eruptive episode with explosive ash emissions — closer to Mayon's magmatic style than Bulusan's.
See all of them on the volcanoes in the Philippines hub, or the global active volcanoes list.
Where Bulusan Sits: Inside the Irosin Caldera
Bulusan is the southernmost volcano on Luzon, at the tip of the Bicol Peninsula in Sorsogon province. It is a 1,535-meter andesitic stratovolcano built on the rim of the 11-kilometer-wide Irosin caldera, which collapsed in a much larger eruption about 36,000 years ago — long before anything in the historical record. The summit holds a 300-meter-wide, 50-meter-deep crater, with three smaller craters on the southeast flank where recent phreatic activity has concentrated. It sits on the Eastern Philippine volcanic arc, where the Philippine Sea Plate subducts beneath the islands — the same Ring of Fire setting that feeds Mayon and Taal. Coordinates: 12.769°N, 124.056°E.
If you live near Bulusan
Stay out of the 4 km Permanent Danger Zone, keep an N95 or P2 mask and clean water on hand for sudden ashfall, and move away from river channels during heavy rain because of lahar risk. A phreatic blast can come with minutes of notice, so follow PHIVOLCS and your local DRRMO rather than waiting for visible signs. Our hazard-by-hazard volcano safety guide covers what to do for ashfall, lahars and gas. Seeing ashfall or feeling a tremor near Sorsogon? Report it to PHIVOLCS — ground observations help refine the warnings.
Frequently Asked Questions
Is Bulusan Volcano erupting right now (November 2026)?
Not in a sustained way — but it is restless. As of the ASEAN AHA Centre's weekly disaster update for November 2–8, 2026, Bulusan sits at Alert Level 1: low-level unrest with an increased chance of sudden steam-driven (phreatic) eruptions. PHIVOLCS raised it to Alert Level 1 on March 22, 2026 after a seismic swarm and ground swelling, and has kept it there through the year. Entry to the 4-kilometer Permanent Danger Zone is prohibited, and PHIVOLCS warns a phreatic blast could happen at any of its summit vents with little or no warning. Always check the latest PHIVOLCS bulletin before relying on this.
How many times has Bulusan erupted?
Our Smithsonian Global Volcanism Program database records 26 eruptions for Bulusan (volcano id 528). Of the 21 that are size-rated, 18 are VEI-2, two are VEI-3 (1979–80 and 1981), and one is VEI-1. It has never produced anything larger than VEI-3. That makes Bulusan a high-frequency, low-magnitude volcano — nine separate eruptive episodes since the year 2000 alone.
How dangerous is Bulusan Volcano?
Bulusan's danger is not its size — it has never exceeded VEI-3 — but its suddenness. Most of its activity is phreatic: groundwater flashing to steam drives an explosion with little or no magmatic warning, so ash columns and ballistic rocks can appear with minutes of notice. That is why PHIVOLCS enforces a 4-kilometer Permanent Danger Zone and a 2-kilometer Extended Danger Zone on the southeast flank even while the alert sits at Level 1. The hazards during these blasts are ashfall, ballistic projectiles, and — after heavy rain — lahars down the river channels.
What is a phreatic eruption?
A phreatic (steam-driven) eruption happens when hot rock flashes groundwater or crater-lake water to steam, blasting out existing ash and rock without fresh magma reaching the surface. Because it needs no new magma to erupt, there is often little of the seismic or deformation build-up that precedes a magmatic eruption — which is exactly why phreatic volcanoes like Bulusan are so hard to forecast and so quick to catch hikers and farmers off guard.
Where is Bulusan Volcano?
Bulusan is in Sorsogon province at the far southeastern tip of Luzon, the southernmost volcano on the island. It is a 1,535-meter stratovolcano built inside the 11-kilometer-wide Irosin caldera, which formed about 36,000 years ago, and it sits on the Bicol segment of the Eastern Philippine volcanic arc. Coordinates: 12.769°N, 124.056°E.