Mount Semeru Erupts Again Tonight, Ash Column Height 1,500 Meters Above Peak

Mount Semeru in East Java erupted again on Saturday (April 11, 2026) at 8:47 PM WIB. In the past week, Mount Semeru has erupted 59 times.

Based on eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the observed ash column height reached 1,500 meters above the peak (5,176 meters above sea level).

The ash column was observed to be white to gray in color with thick intensity towards the northwest. The eruption was recorded on the seismograph with a maximum amplitude of 22 millimeters and a duration of 241 seconds.

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According to the MAGMA Indonesia volcano activity report, Mount Semeru's activity level is at Level III (Alert). Earthquake observations on April 11, 2026 from 12:00 PM to 6:00 PM WIB showed 19 eruption/explosion earthquakes with amplitudes of 10-22 millimeters and durations of 51-170 seconds.

Then, 7 emission earthquakes with amplitudes of 2-8 millimeters and durations of 49-87 seconds, as well as 5 harmonic earthquakes with amplitudes of 1-4 millimeters and durations of 63-452 seconds.

PVMBG advises against any activities in the southeast sector along the Besuk Kobokan, up to 13 kilometers from the peak (eruption center). Beyond that distance, residents are advised not to conduct activities within 500 meters of the riverbank along the Besuk Kobokan due to the potential for being affected by expanding pyroclastic flows and lahar flows up to 17 kilometers from the peak.

During 2026, MAGMA Indonesia has recorded 1,421 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions with 767 events.

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