Mount Semeru Erupts Again This Afternoon (Wednesday, December 17, 2025)

Mount Semeru in East Java erupted again on Wednesday (17/12/2025) at 12:30 PM WIB. In the last week, Mount Semeru has erupted 13 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 observed reached None meters above the peak or None meters above sea level.

No visual eruption was observed. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 110 seconds.

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According to MAGMA Indonesia's volcano activity report, Mount Semeru's activity level is at Level III (Alert). Seismicity observations on December 17, 2025, from 06:00 AM to 12:00 PM WIB showed 29 eruption/explosion earthquakes with amplitudes of 10-23 millimeters and durations of 55-143 seconds.

Additionally, there was 1 rockfall earthquake with an amplitude of 6 mm and a duration of 43 seconds, and 2 shallow gas emission earthquakes with amplitudes of 4-6 millimeters and durations of 56-68 seconds.

PVMBG advises against any activity in the southeast sector along Besuk Kobokan, as far as 13 kilometers from the peak (eruption center). Beyond that distance, the public should not engage in activities within 500 meters from the riverbanks (river borders) along Besuk Kobokan due to the potential for hot cloud expansion and lahars up to 17 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 7,370 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 3,037 events.

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