Mount Semeru Erupts Again This Afternoon (Tuesday, August 26, 2025)

Mount Semeru in East Java erupted again on Tuesday (8/26/2025) at 1:41 PM WIB. In the last week, Mount Semeru has erupted 13 times.

Reporting 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 None meters above the peak (None meters above sea level).

No visual eruption was observed. Mount Semeru''s eruption was still ongoing when this report was made.

(Read: Jakarta''s Air Quality is Poor, Losing to Other ASEAN Capitals)

According to MAGMA Indonesia''s volcano 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 earthquake durations of 51-178 seconds.

Additionally, 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, up to 8 kilometers from the peak (eruption center). Beyond that distance, people should not conduct activities within 500 meters from the riverbanks (river border) along Besuk Kobokan due to the potential for hot clouds and lava flows to extend up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 5,812 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most with 2,322 times.

(Read: Air Quality in Indonesia Slightly Improved in 2021)