Warning! Mount Semeru Erupts Again This Afternoon (Monday, December 8, 2025)

Mount Semeru in East Java erupted again on Monday (12/8/2025) at 11:37 AM WIB. In the last week, Mount Semeru has erupted 7 times.

Citing eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the height of the ash column was observed to reach None meters above the peak (None meters above sea level).

Visual of the eruption was not observed. The Mount Semeru eruption was still ongoing when this report was made.

(Read: Indonesia's Air Quality Worst in ASEAN in 2022)

According to MAGMA Indonesia's volcano activity report, Mount Semeru's activity level is at Level III (Alert). Seismicity observations on December 8, 2025, from 00:00-06:00 WIB, showed 41 eruption earthquakes with amplitudes of 10-22 millimeters and earthquake durations of 62-180 seconds.

Subsequently, there were 2 rockfall earthquakes with amplitudes of 8-10 mm and durations of 44-79 seconds, and 2 exhalation earthquakes with amplitudes of 6-8 millimeters and durations of 62-65 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 expansion of hot clouds and lava flows up to 17 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 7,260 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most with 2,985 times.

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