Mount Semeru Erupts Again This Afternoon, Volcanic Ash Plume Approximately 700 Meters High

Mount Semeru in East Java erupted again on Friday (31/10/2025) at 17:19 WIB. In the last week, Mount Semeru has erupted 47 times.

Based on eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the height of the observed ash column reached 700 meters above the peak (4,376 meters above sea level).

The ash column was observed to be white to grey with thick intensity towards the north. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 135 seconds.

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According to MAGMA Indonesia's volcano activity report, Mount Semeru's activity level is at Level II (Alert). Seismicity observations on October 31, 2025, from 00:00-23:59 WIB showed 137 eruption earthquakes with amplitudes of 10-22 millimeters and durations of 52-208 seconds.

Furthermore, there were 37 rockfall earthquakes with amplitudes of 2-15 mm and durations of 21-159 seconds, and 6 emission earthquakes with amplitudes of 3-7 millimeters and durations of 35-57 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 of the riverbanks (river border) 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 6,854 volcano eruptions across Indonesia. Mount Semeru in East Java has erupted the most with 2,730 times.

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