Mount Semeru Erupts Again This Afternoon, Ash Plume 500 Meters Above Peak

Mount Semeru in East Java erupted again on Saturday (09/13/2025) at 3:14 PM WIB. In the last week, Mount Semeru has erupted 36 times.

Based on eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the ash column was observed to be approximately 500 meters above the peak (4,176 meters above sea level).

The ash column was observed to be white to gray with thick intensity towards the north and northwest. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 115 seconds.

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According to the MAGMA Indonesia volcano activity report, Mount Semeru''s activity level is at Level II (Alert). Seismic observations on September 13, 2025, from 00:00-23:59 WIB showed 55 eruption tremors with amplitudes of 12-22 millimeters and durations of 49-217 seconds.

Then, 5 rockfall tremors with amplitudes of 3-7 mm and durations of 64-128 seconds, and 2 exhalation tremors with an amplitude of 5 millimeters and durations of 38-40 seconds occurred.

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 riverbanks (river borders) along Besuk Kobokan, as there is a potential for hot clouds and lava flows to extend up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,079 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most with 2,438 occurrences.

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