Volcanic activity at Mount Semeru showed a significant increase on Sunday (28/6/2026) morning. Based on monitoring from the Mount Semeru Observation Post, the highest mountain on the island of Java recorded five consecutive eruptions between 00:00 and 06:00 WIB.
Sigit Rian Alfian, an officer at the Mount Semeru Observation Post, confirmed that a column of volcanic ash was observed rising up to 1,200 meters above the peak. Visual reports showed the ash column was white to gray in color with thick intensity, moving to the west and northwest.
Volcano monitoring authorities have now issued an alert status for residents around the slopes. The public is urged to refrain from any activities within a 13-kilometer radius from the eruption center to anticipate safety risks.
In addition to the threat of volcanic ash, residents living along the river basins originating from Mount Semeru are asked to increase extra vigilance against the potential for hot cloud avalanches and cold lava flows that could occur at any time due to the accumulation of volcanic material at the peak.
