Mount Semeru Erupts Again Tonight, Ash Plume 900 Meters Above Peak

Mount Semeru in East Java erupted again on Wednesday (7/1/2026) at 23:57 WIB. In the last week, Mount Semeru has erupted 30 times.

Based on eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the height of the ash column was observed to be around 900 meters above the peak or 4,576 meters above sea level.

The ash column was observed to be white to grey with moderate intensity towards the north. Mount Semeru's eruption was still ongoing when this report was made.

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According to the MAGMA Indonesia volcano activity report, Mount Semeru's activity level is at Level III (Alert). Seismic observations on January 7, 2026, at 12:00-18:00 WIB showed 22 eruption earthquakes with amplitudes of 11-22 millimeters and durations of 65-108 seconds.

Additionally, there were 7 exhalation earthquakes with amplitudes of 4-7 millimeters and durations of 40-72 seconds, and 1 harmonic earthquake with an amplitude of 2 millimeters and a duration of 181 seconds.

PVMBG urges against any activities in the southeast sector along Besuk Kobokan, as far as 13 kilometers from the peak (eruption center). Beyond that distance, people should not engage in activities within 500 meters of the riverbank (river boundary) along Besuk Kobokan due to the potential for expansion of hot clouds and lava flows up to 17 kilometers from the peak.

Throughout 2026, MAGMA Indonesia has recorded 111 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most, with 67 occurrences.

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