Mount Semeru Erupts Again This Afternoon (Saturday, August 23, 2025)

Mount Semeru in East Java erupted again on Saturday (8/23/2025) at 3:40 PM WIB. In the last week, Mount Semeru has erupted 27 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 be around None meters above the peak or None meters above sea level.

No visual eruption was observed. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 134 seconds.

(Read: Not Jakarta, These Are the Areas with the Worst Air Quality in Indonesia (Wednesday, June 7, 2023))

According to MAGMA Indonesia''s volcano activity report, Mount Semeru''s activity level is at Level II (Alert). Seismicity observations on August 23, 2025, from 00:00-23:59 WIB showed 51 eruption tremors/earthquakes with amplitudes of 10-22 millimeters and a duration of 40-220 seconds.

Furthermore, there were 3 rockfall tremors with amplitudes of 3-5 mm and a duration of 54-91 seconds, and 5 exhalation tremors with amplitudes of 3-8 millimeters and a duration of 48-90 seconds.

PVMBG advises against any activity in the southeast sector along Besuk Kobokan, as far as 8 kilometers from the peak (eruption center). Beyond this distance, people should not engage in activities within 500 meters from the riverbanks (river border) along Besuk Kobokan, as there is a potential for hot cloud expansion and lava flow up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 5,752 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 2,302 occurrences.

(Read: Jakarta''s Air Quality This Morning Ranked Third Worst in the World (Tuesday, June 6, 2023))