Warning! Mount Semeru Erupts Again This Morning (Thursday, October 9, 2025)

Mount Semeru in East Java erupted again on Thursday (9/10/2025) at 09:28 AM WIB. In the last week, Mount Semeru has erupted 31 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 was approximately 500 meters above the peak (4,176 meters above sea level).

The ash column was observed to be white to grey with thick intensity towards the southwest. 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 volcanic activity report, Mount Semeru's activity level is at Level II (Alert). Seismic observations on October 9, 2025, from 00:00-23:59 WIB showed 94 eruption/explosion earthquakes with amplitudes of 10-22 millimeters and earthquake durations of 50-197 seconds.

Furthermore, there were 2 rockfall earthquakes with amplitudes of 6-7 mm and durations of 49-125 seconds, and 9 emission earthquakes with amplitudes of 4-8 millimeters and durations of 39-62 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 from the riverbanks (river borders) along Besuk Kobokan due to the potential for being affected by the expansion of hot clouds and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,594 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most, with 2,592 occurrences.

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