Volcanic activity at Mount Semeru in East Java showed another significant increase on Saturday, July 4, 2026. At precisely 06:08 WIB, the highest volcano on Java Island erupted, spewing a column of volcanic ash 1,400 meters above its peak. Based on visual observations, the ash column was of medium intensity, ranging from white to gray, and was observed moving toward the south.
The Center for Volcanology and Geological Hazard Mitigation (PVMBG) recorded the eruption on a seismogram with a maximum amplitude of 22 millimeters. The duration of this seismic activity lasted for 2 minutes and 17 seconds. To date, authorities continue to monitor the volcano's activity to anticipate potential further hazards for surrounding areas.
Mount Semeru's status currently remains at Level III (Alert). As a mitigation measure, PVMBG has strictly prohibited the public from conducting any activities in the southeastern sector along Besuk Kobokan within a 13-kilometer radius from the eruption center. In addition, the public is advised to maintain a safe distance of 500 meters from the riverbanks along Besuk Kobokan to avoid the threat of pyroclastic flows and cold lava flows.
Furthermore, a total exclusion zone has also been established within a 5-kilometer radius from the main crater due to the high risk of incandescent rock projectiles. Residents are strongly urged to stay away from river channels originating at the peak, such as Besuk Bang, Besuk Kembar, and Besuk Sat, to minimize the risk of casualties from lava flows and other volcanic material.
