Warning! Mount Semeru Erupts Again Tonight (Tuesday, September 9, 2025)

Mount Semeru in East Java erupted again on Tuesday (9/9/2025) at 8:10 PM WIB. In the last week, Mount Semeru has erupted 16 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 (None meters above sea level).

The visual of the eruption was not observed. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 138 seconds.

(Read: Flood Disaster Events in Indonesia Increased Period 2008-2025)

According to MAGMA Indonesia''s volcano activity report, Mount Semeru''s activity level is at Level II (Alert). Seismic observations on September 9, 2025, from 00:00-23:59 WIB showed 54 eruption/explosion earthquakes with amplitudes of 12-22 millimeters and earthquake durations of 56-189 seconds.

Then, 5 rockfall earthquakes with amplitudes of 3-5 mm and durations of 41-68 seconds, and 14 exhalation earthquakes with amplitudes of 3-9 millimeters and durations of 36-65 seconds occurred.

PVMBG urges not to carry out any activities 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 river bank (river border) along Besuk Kobokan because of the potential for being affected by the expansion of hot clouds and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,032 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions with 2,418 times.

(Read: Despite the Dry Season, Many Flood Disasters in Early July 2024)