The ashfall from Mayon Volcano that blanketed several towns in Albay covers an area roughly half the size of Quezon City, the Philippine Space Agency said.
“Based on the analysis, at least 8,544 hectares were covered by ashfall. For comparison, this area is around half the size of Quezon City,” PhilSA said in a statement.
The agency said it used satellite imagery from Sentinel-2 to conduct change detection analysis, comparing images taken on May 4, 2026, and April 28, 2026, to identify ash-covered areas.
“For areas obstructed by cloud cover, ash deposition cannot be directly determined,” it said.
“However, the ash deposit extent could be extrapolated by delineating a region around areas classified to have ash deposits. These results are consistent with projections from atmospheric trajectory modeling and reports from the ground. The map is still subject to ground validation,” PhilSA added.
On May 2, a pyroclastic density current, or “uson,” was observed at Mayon Volcano, affecting more than 30,000 families, or around 100,000 individuals, as well as plantations and livestock. — Photo from Mayor Caloy Baldo
