Mount Semeru Erupts Again Tonight (Tuesday, August 26, 2025)

Mount Semeru in East Java erupted again on Tuesday (26/8/2025) at 8:58 PM WIB. In the last week, Mount Semeru has erupted 18 times.

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 or None meters above sea level.

The eruption was not visually observed. The eruption was recorded on a seismograph with a maximum amplitude of 20 millimeters and a duration of 150 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 August 26, 2025, from 00:00-23:59 WIB showed 41 eruption/explosion earthquakes with amplitudes of 10-22 millimeters and durations of 51-178 seconds.

Furthermore, there were 5 rockfall earthquakes with amplitudes of 2-8 mm and durations of 50-81 seconds, and 12 exhalation earthquakes with amplitudes of 2-8 millimeters and durations of 27-95 seconds.

PVMBG advises against any activities in the southeast sector along Besuk Kobokan, as far as 8 kilometers from the peak (eruption center). Beyond that distance, the public should not engage in activities within 500 meters of the riverbanks (river borders) along Besuk Kobokan due to the potential for being affected by expanding hot clouds and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 5,818 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most, with 2,327 occurrences.

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