Mount Semeru Erupts Again Early This Morning, Ash Plume Around 500 Meters High

Mount Semeru in East Java erupted again on Monday (27/10/2025) at 02:01 AM WIB. In the last week, Mount Semeru only erupted once.

Based on eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the observed ash column reached 500 meters above the peak (4,176 meters above sea level).

The ash column was observed to be white to grey with thick intensity towards the southwest and west. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 142 seconds.

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According to MAGMA Indonesia's volcanic activity report, Mount Semeru's activity level is at Level II (Alert). Seismic observations on October 27, 2025, from 00:00-23:59 WIB, showed 119 eruption earthquakes with amplitudes of 10-23 millimeters and durations of 58-167 seconds.

Subsequently, there were 7 rockfall earthquakes with amplitudes of 2-6 mm and durations of 47-75 seconds, and 24 emission earthquakes with amplitudes of 3-8 millimeters and durations of 24-71 seconds.

PVMBG advises against any activity in the southeast sector along Besuk Kobokan, as far as 8 kilometers from the peak (eruption center). Beyond that distance, people should not engage in activities within 500 meters from the riverbanks (river borders) along Besuk Kobokan due to the potential for expansion of hot clouds and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,789 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most, with 2,684 eruptions.

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