Warning! This Morning Mount Semeru Erupts Again (Wednesday, August 13, 2025)

Mount Semeru in East Java erupted again on Wednesday (8/13/2025) at 09:38 AM WIB. In the last week, Mount Semeru has erupted 20 times.

Based on 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 reach 1,000 meters above the peak (4,676 meters above sea level).

The ash column was observed to be white to gray with thick intensity towards the south and southwest. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 138 seconds.

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According to MAGMA Indonesia's volcano activity report, Mount Semeru's activity level is at Level II (Alert). Seismicity observations on August 13, 2025, from 00:00-23:59 WIB showed 53 eruption tremors/earthquakes with amplitudes of 10-22 millimeters and durations of 58-191 seconds.

Furthermore, there were 2 rockfall earthquakes with an amplitude of 2 mm and durations of 82-93 seconds, and 11 gas emission earthquakes with amplitudes of 4-8 millimeters and durations of 32-162 seconds.

PVMBG urges 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 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 5,591 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most with 2,237 occurrences.

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