Warning! Mount Semeru Erupts Again This Afternoon (Monday, September 29, 2025)

Mount Semeru in East Java erupted again on Monday (9/29/2025) at 11:58 AM WIB. In the last week, Mount Semeru has erupted 8 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.

The visual eruption was not observed. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 119 seconds.

(Read: Jakarta's Air Quality This Morning is the Second Worst in the World (Friday, June 17, 2022))

According to MAGMA Indonesia's volcanic activity report, Mount Semeru's activity level is at Level II (Alert). Seismicity observations on September 29, 2025, from 00:00-23:59 WIB showed 76 eruption earthquakes with amplitudes of 11-22 millimeters and durations of 47-138 seconds.

Furthermore, there was 1 rockfall earthquake with an amplitude of 4 mm and a duration of 51 seconds, and 16 exhalation earthquakes with amplitudes of 4-8 millimeters and durations of 30-64 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 (river border) along Besuk Kobokan due to the potential for hot cloud expansion and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,438 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 2,530 events.

(Read: Jatibening Included in the List of 15 Areas with the Best Air Quality in Indonesia as of September 2023)