Mount Semeru Erupts Again Tonight (Monday, September 8, 2025)

Mount Semeru in East Java erupted again on Monday (September 8, 2025) at 00:31 WIB. In the last week, Mount Semeru has erupted twice.

According to 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 be around None meters above the peak (None meters above sea level).

Eruption visuals were not observed. Mount Semeru''s eruption was still ongoing when this report was made.

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According to MAGMA Indonesia''s volcanic activity report, Mount Semeru''s activity level is at Level II (Alert). Seismicity observations on September 8, 2025, from 00:00-23:59 WIB showed 56 eruption tremors/earthquakes with amplitudes of 10-22 millimeters and durations of 42-250 seconds.

Additionally, there were 2 rockfall tremors with an amplitude of 2 mm and durations of 92-107 seconds, and 15 exhalation tremors with amplitudes of 2-8 millimeters and durations of 8-13 seconds.

PVMBG advises against any activity in the southeast sector along Besuk Kobokan, as far as 8 kilometers from the peak (eruption center). Beyond that distance, people should not engage in activities within 500 meters of the riverbank (river boundary) along Besuk Kobokan as it has the potential to be affected by the expansion of hot clouds and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,003 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 2,404 occurrences.

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