LEGAZPI CITY — The Philippine Institute of Volcanology and Seismology announced on Friday that it has lowered Mt. Mayon's alert status from Level 3 to 2 due to declining parameters in volcanic activities.

In its 8 December bulletin, Phivolcs said the lowering of the alert level was supported by different parameters and observations.

Level 3 means a hazardous eruption is possible while Level 2 signifies moderate unrest.

It added that seismic activities have declined from a monthly average of 11 volcanic earthquakes in November to zero in the first week of December. Volcanic earthquakes are typically attributed to rock fracturing beneath the edifice and occasional rockfall.

The overall low-level seismicity signifies that the magma supply to the summit crate has significantly reduced.

Meantime, the sulfur gas output has decreased from an average of 4,756 tons per day on 16 August to 859 tons per day on 7 December.

The overall low level of SO2 gas emission indicates that the volcanic gas from lava exposed on the crater and slopes of Mayon and from magma stored within the volcano is declining.

Phivolcs said that visual observation of the summit recorded lessening incandescence of the summit crater and the 2023 lava flow deposits since the last week of November.

In its ground deformation, data from continuous global positioning system and electronic distance meter measurements and radial tilt indicated asymmetric deformation of the Mayon edifice throughout its period of unrest.

However, Phivolcs reminded the public that lowering the alert status should not be interpreted as the end of the volcano's unrest.

"Considering that the edifice is still inflated and SO2 emission remains high relative to baseline levels. The public is strongly advised to be vigilant and to avoid entry into the 6-km Permanent Danger Zone to minimize risks from explosions, rockfalls and landslides," said the agency.

To recall, Mayon Volcano's alert level was raised to 3 in June this year, prompting the local government units to evacuate 5,672 families in Camalig, Daraga, Guinobatan, Ligao City, Tabaco City, Malilipot, and Sto. Domingo.