Three one-minute phreatic eruptions were observed in Taal Volcano within 24 hours by the Philippine Institute of Volcanology and Seismology (Phivolcs).
The phreatic eruptions occured at 7:15 p.m., 7:19 p.m., and 7:23 p.m.
State volcanologists also recorded three volcanic earthquakes.
Taal's main crater emitted 3,309 tons of volcanic sulfur dioxide on 2 August, and a volcanic smog was observed.
A 2,100-meter-tall plume described as a "voluminous emission," was also reported on Friday, which drifted southeast.
Long-term deflation of the Taal caldera was observed, accompanied by short-term inflation of the general northern and southeastern flanks of Taal Volcano Island.
Sudden explosions, volcanic earthquakes, minor ashfall, and lethal accumulations or expulsions of volcanic gas posed serious health and safety risks, Phivolcs warned.
Entry into Taal Volcano Island, particularly in the main crater and Daang Kastila fissures, remains strictly prohibited. The island has been identified as a permanent danger zone.
Aircraft flying close to the volcano, Phivolcs said, are at risk of coming into contact with airborne ash and ballistic fragments.
Taal Volcano is still under alert level 1, indicating low level unrest.