Mount Semeru, located in East Java, showed volcanic activity once again on Friday, July 3, 2026. According to a report from the Center for Volcanology and Geological Hazard Mitigation (PVMBG), the eruption occurred precisely at 07:29 WIB, spewing a volcanic ash column approximately 1,100 meters above the summit.
The observed ash column varied in color from white to gray with medium intensity, drifting towards the south. Seismogram data recorded a maximum amplitude of 22 mm with an initial duration of about two minutes, and the release of volcanic material was reported to be ongoing following the event.
As of now, Mount Semeru's alert status remains at Level III (Alert). PVMBG has strictly issued recommendations for the public not to conduct any activities in the southeastern sector along Besuk Kobokan within a 13-kilometer radius from the eruption center. This restriction aims to minimize the risk of casualties from pyroclastic flows and lahar flows.
Beyond that area, residents are also urged to stay clear of a 500-meter radius from the riverbanks along Besuk Kobokan, as the potential expansion of pyroclastic flows could reach up to 17 kilometers from the summit. Additionally, the public is asked to maintain a 5-kilometer distance from the main crater to avoid the hazard of incandescent rock projectiles that could occur at any time.
Authorities continue to remind residents living near river valleys originating from Mount Semeru, such as Besuk Bang, Besuk Kembar, and Besuk Sat, to heighten vigilance against cold lahar floods, especially when heavy rainfall hits the summit area.
