Alert level 1 means that it is thought that presently no magmatic eruption is imminent, but it is strongly advised to stay out of a radius of 6 km around the volcano because of the danger of sudden (phreatic) explosions as well as rockfalls and landslides and mud flows during heavy rainfall. [less]

On the other hand, SO2 and seismic parameters have not shown a significant increase, which probably means that an eruption is not imminent.
However, as the deadly phreatic eruption on 7 May illustrated, sudden explosions can occur any time without particular precursory signs. [less]

The victims, many foreigners, were part of an organized group of climbers. They were surprised by the explosion that showered the camp area with ballistic blocks that hit them.
The eruption itself produced a large ash-plume rising several hundred meters before dispersing. [less]

PHILVOLCS has been recording few, but more than background numbers of volcanic earthquakes under the volcano recently. Visible activity consists of the emission of white steam plumes. Cater glow if any could not be observed due to cloud cover of the summit area.
The SO2 emission rate was last measured on 01 November 2012 at an average of 153 tonnes per day. Ground deformation by precise leveling between Aug 2011 and May 2012, as well as tile and GPS data between May and Aug 2012 indicated slight inflation of the lower and deflation of the upper slopes. [less]

The latest PHIVOLCS update reports little to no seismicity, SO2 emissions below 100 tonnes/day and no deformation measured since February. [less]

Authorities have raised the alert level to 3 (out of 4) and started to evacuate 50,000 people living in the immediate neighborhood of the volcano. [less]

PHIVOLCS reported on 1 October that fumarolic activity from Mayon produced steam plumes that drifted ENE. Intense incandescence was observed at the summit. Observations were not possible 2-3 October due to cloud cover. According to news articles, the Alert Level was lowered to 2 on 3 October.

Volcanic activity at Mayon consisted of incandescent lava fragments rolling down the slopes and glow coming from the summit crater. Moderate white steam emissions continued from the summit. The number of daily volcanic earthquakes was low during 20-24 September, with 1-3 events per day.

Seismic activity and lava extrusion from Mayon decreased during 6-12 September. Ground-deformation measurements showed an overall deflation. On 11 September, the Alert Level was lowered from 4 to 3 and around 30,000 people who had been evacuated early in August were allowed to return to their homes.

Thick blocky lava lava continues to flow from Mayon volcano. The main active flow on the SE slope reaches about 800 m elevation where the flow front begins to disintegrate into loose blocks that roll into the Buyoan ravine.
Occasional explosions at Mayon continued during the past weeks. According to seismic data, four explosions were registered on 31 August. Ashfall was reported in surrounding cities including Tabaco (about 13 km NW) and Guinobatan (about 13 km SW). One small explosion was registered on 3 September.

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PHIVOLCS reported that explosions from Mayon continued during 16-19 August.
On 17 August, ash-and-steam plumes drifted at least 5.3 km NE and reached the town Calbayog, where light ashfall was reported. Lava extrusion and collapsing lava-flow fronts that produced blocks and small fragments on the SE slopes continued during the reporting period.
On 18 August, the Mibinit/Bonga valley lava flows reached ~6.8 km SE from the summit. The following day, PHIVOLCS estimated that the volume of erupted volcanic deposits was 36 to 41 million cubic meters.

During 9-15 August, explosive activity continued at Mayon after a brief respite on 8 August. Based on interpretations of seismic data, minor explosions during 9-11 and 13-15 August were accompanied by lava extrusion and collapsing lava flow fronts that produced blocks and small fragments. Visual observations were usually obscured by clouds, but on 11 August an ash plume was seen drifting ESE. On 12 August, out of four explosions that occurred, one produced a pyroclastic flow that traveled over the SE and E slopes and generated a plume that rose 500 m high and drifted NE. On 15 August, a brief break in the clouds allowed for a view and confirmation of fresh pyroclastic deposits from activity the previous days.
About 40,000 people remained in evacuation centers. The Extended Danger Zone of 8 km in the SE sector was still in effect.

PHIVOLCS reported that during 2-8 August, lava from Mayon continued to flow mainly SSE along the Mabinit channel and subsequently over a broad sector of the upper and middle SE slopes.
During 17 July-3 August, the volume of lava discharged amounted to 17 million cubic meters.Voluminous steaming accompanied lava extrusion.
On 4 August, lava flows extended 30 m beyond the 6-km-radius region designated as the Permanent Danger Zone.
Areas SE and E experienced light ash fall on 4 August generated by the collapse of deposits.
On 6 August, lava flows spilled into the Bonga Valley, E of the Mabinit Chanel.
The Tokyo VAAC reported an eruption cloud at 2331 that reached an altitude of 3.4 km (11,000 ft) a.s.l. and drifted E. On 7 August, the Alert Level was raised to 4 (scale is 0-5, 0 referring to No Alert status) and the Extended Danger Zone (8 km from the summit) was defined.
Three explosions (out of nine in a 24-hour period) at 22:36, 22:46, and 22:49 produced incandescent ejections of lava fragments, ash, gas, and steam.
According to news reports, ~40,000 people were evacuated from inside the Extended Danger Zone to 20 evacuation centers on 7 and 8 August.
A bigger explosion is expected in the next days or weeks.

Lava flows from Mayon in the SE sector of the Bonga gully advanced ~1.35 km during 26 July-1 August to reach a maximum distance of 5.8 km SSE from the summit on 1 August. Smaller lava flows and incandescent blocks descended adjacent gullies. On July 29, light ash accumulation was reported about 12 km S and SE, in Daraga municipality and Legazpi City and vicinity, respectively. Emissions of sulfur-dioxide reached ~12,500 tons per day on 31 July, a record high for the current period of unrest.

Lava flows from Mayon traveled SSE a maximum distance of 4 km from the summit toward the Bonga gully and branched off to the W and E. Incandescent blocks shed from the toe and margins of the flows were visible at night and traveled SE. Ash plumes generated from the rolling blocks produced light ash fall 8.5 km E of the summit in Sta. Misericordia. On 20 July, pyroclastic flows were observed on the SE slopes prompting ~100 families to evacuate. On 22 July, lava flows advanced NE towards the Mabinit channel. The lava flows were within the 6 km radius Permanent Danger Zone.

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The number and size of incansecent rock falls from the active lava dome as well as SO2 emission at Mayon volcano are increasing according to the observatory, that maintains that pyroclastic flows or an explosive eruption can occur any time now. The volcano is at alert level 3 with a non-enforced exclusion zone of 6 km around the summit.