Mount Semeru, located in Lumajang Regency, East Java, showed significant volcanic activity again on Wednesday morning (1/7/2026). The Center for Volcanology and Geological Hazard Mitigation (PVMBG) recorded the eruption taking place at exactly 09:24 WIB, with the ash column reaching 1,000 meters above the peak, or approximately 4,676 meters above sea level.
Based on observation reports, the ash column appeared white to gray with thick intensity moving to the east and southeast. This eruption was recorded on a seismograph with a maximum amplitude of 22 mm and a duration of 103 seconds. In 2026 alone, the highest mountain on Java Island has erupted 1,380 times.
An officer at the Mount Semeru Monitoring Post, Sigit Rian, emphasized that both residents and tourists must stay away from the southeastern sector along Besuk Kobokan up to a radius of 13 km from the eruption center. In addition, the public is prohibited from engaging in activities within a 5 km radius of the crater due to the high risk of incandescent rock ejection.
To date, Mount Semeru's status remains at Level III (Alert). PVMBG continues to warn of secondary hazards such as pyroclastic flows, lava drops, and lahars that could threaten river valleys originating from the peak, such as Besuk Bang, Besuk Kembar, and Besuk Sat. The public is requested to remain vigilant and comply with instructions from field officials for mutual safety.
