Mount Semeru Erupts Again This Afternoon (Monday, October 6, 2025)

Mount Semeru in East Java erupted again on Monday (October 6, 2025) at 12:26 PM WIB. In the last week, Mount Semeru has erupted 3 times.

Citing 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.

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

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According to the MAGMA Indonesia volcano activity report, Mount Semeru's activity level is at Level II (Alert). Seismicity observations on October 6, 2025, from 00:00-23:59 WIB showed 94 eruption tremors/earthquakes with amplitudes of 10-23 millimeters and earthquake durations of 40-202 seconds.

Then, 1 rockfall earthquake with an amplitude of 5 mm and an earthquake duration of 66 seconds, and 4 exhalation earthquakes with amplitudes of 4-6 millimeters and earthquake durations of 37-95 seconds.

PVMBG urged not to carry out any activities in the southeast sector along Besuk Kobokan, as far as 8 kilometers from the peak (eruption center). Beyond that distance, the public is advised not to carry out 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 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,550 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions with 2,564 events.

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