Mount Semeru Erupts Again Tonight (Friday, November 21, 2025)

Mount Semeru in East Java erupted again on Friday (11/21/2025) at 18:54 WIB. In the last week, Mount Semeru has erupted 15 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 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 116 seconds.

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According to MAGMA Indonesia's volcano activity report, Mount Semeru's activity level is at Level IV (Alert). Seismicity observations on November 21, 2025, from 12:00-18:00 WIB, showed 42 eruption/explosion earthquakes with amplitudes of 12-22 millimeters and durations of 71-180 seconds.

Additionally, there were 5 rockfall earthquakes with amplitudes of 2-3 mm and durations of 68-84 seconds, and 1 flood tremor earthquake with an amplitude of 43 millimeters and a duration of 6499 seconds.

PVMBG advises against any activity in the southeast sector along Besuk Kobokan, as far as 20 kilometers from the peak (eruption center). Beyond this distance, people should not conduct activities within 500 meters from the riverbanks along Besuk Kobokan due to the potential for expansion of hot clouds and lava flows.

Throughout 2025, MAGMA Indonesia has recorded 7,006 volcanic eruptions across Indonesia. Mount Semeru in East Java has had the most eruptions, with 2,809 events.

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