Mount Semeru Erupts Again This Afternoon, Ash Column Reaches 700 Meters Above Peak

Mount Semeru in East Java erupted again on Tuesday (23/12/2025) at 17:51 WIB. In the past week, Mount Semeru has erupted 24 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 was approximately 700 meters above the peak or 4,376 meters above sea level.

The ash column was observed to be white to grey with thick intensity towards the north and northeast. The eruption was recorded on a seismograph with a maximum amplitude of 15 millimeters and a duration of 85 seconds.

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According to the MAGMA Indonesia volcano activity report, Mount Semeru's activity level is at Level III (Alert). Seismicity observations on December 23, 2025, from 06:00-12:00 WIB showed 38 eruption earthquakes with amplitudes of 10-23 millimeters and durations of 77-148 seconds.

Additionally, there was 1 rockfall earthquake with an amplitude of 3 mm and a duration of 45 seconds, and 4 emission earthquakes with amplitudes of 6-8 millimeters and durations of 54-93 seconds.

PVMBG advises against any activity in the southeastern 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 riverbanks (river borders) along Besuk Kobokan, as there is a potential for expansion of hot clouds and lava flows up to 17 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 7,494 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 3,122 events.

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