Mount Semeru Erupts Again Tonight (Thursday, July 31, 2025)

Mount Semeru in East Java erupted again on Thursday (July 31, 2025) at 23:39 WIB. In the last week, Mount Semeru has erupted 21 times.

Based on eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the observed ash column height reached not observed meters above the peak (not observed meters above sea level).

Visual eruption was not observed. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 117 seconds.

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According to the MAGMA Indonesia volcano activity report, the activity level of Mount Semeru is at Level II (Alert). Seismic observations on July 31, 2025, from 00:00-23:59 WIB showed 40 eruption earthquakes with amplitudes of 10-22 millimeters and a duration of 41-175 seconds.

Followed by 2 rockfall earthquakes with amplitudes of 5-6 mm and a duration of 36-57 seconds, and 5 exhalation earthquakes with amplitudes of 3-6 millimeters and a duration of 34-148 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, the public 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 5,396 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most with 2,166 times.

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