After two explosions, Bulusan goes on alert level 1.

Bulusan summit - archive photo USGS / Newhall

The Bulusan, located in the province of Sorsogon in the Philippine archipelago, is raising on alert 1 / abnormal, following an explosion May 6, 2015 at 9:46 p.m.. It lasted after 3.5 minutes depending on the seismic records. Initially from a vent on the upper northwest slopes, an ash plume rose to about 250 meters before drifting westwards. Ash falls were reported in Brgy. Bagsangan, Cogon, Monbon and Tinampo / Irosin, Sorsogon. This episode follows an explosion at the same vent on May 1, which lasted 5 minutes.
This type of explosion is typical of Bulusan during periods of rest, when disruptions mark the hydrothermal system, or when the steam pressure builds up on a superficial level.
A "no-go" 4 km-radius zone was established.
The situation is not favorable to the approach of the archipelago by the Dodong typhoon, the rain could mobilize the ash deposits.

Sources:
Phivolcs
CNN Philippines

Bulusan location in the Philippine archipelago

Bulusan hazards map / GVP