Mount Semeru Erupts Again This Afternoon (Monday, August 25, 2025)

Mount Semeru in East Java erupted again on Monday (August 25, 2025) at 4:01 PM WIB. In the last week, Mount Semeru has erupted 4 times.

Citing eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the height of the ash column observed was approximately 600 meters above the peak or 4,276 meters above sea level.

The ash column was observed to be grey with thick intensity towards the north. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 107 seconds.

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According to MAGMA Indonesia''s volcano activity report, the activity level of Mount Semeru is at Level II (Alert). Seismic observations on August 25, 2025, from 00:00-23:59 WIB showed 44 eruption tremors with amplitudes of 10-22 millimeters and tremor durations of 54-183 seconds.

Then, 5 avalanche tremors with amplitudes of 2-6 mm and tremor durations of 49-90 seconds, and 14 exhalation tremors with amplitudes of 3-9 millimeters and tremor durations of 35-90 seconds occurred.

PVMBG urges people 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, people should not engage in activities within 500 meters of the riverbanks along Besuk Kobokan, as there is a potential for expansion of hot clouds and lahars up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 5,792 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 2,313 incidents.

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