Warning! Mount Semeru Erupts Again This Morning (Wednesday, September 17, 2025)

Mount Semeru in East Java erupted again on Wednesday (9/17/2025) at 08:41 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 observed reached None meters above the peak (None 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 122 seconds.

(Read: Air Quality in Major Indonesian Cities is Poor, Far from WHO Standards)

According to MAGMA Indonesia''s volcanic activity report, Mount Semeru''s activity level is at Level II (Alert). Seismic observations on September 17, 2025, from 00:00-23:59 WIB showed 54 eruption earthquakes with amplitudes of 10-22 millimeters and durations of 50-225 seconds.

Furthermore, 9 rockfall earthquakes with amplitudes of 2-8 mm and durations of 48-114 seconds, and 8 emission earthquakes with amplitudes of 4-8 millimeters and durations of 35-71 seconds occurred.

PVMBG urges not to conduct 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 riverbanks along Besuk Kobokan, as there is a potential for hot cloud expansion and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,126 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 2,455 occurrences.

(Read: Indonesia''s Air Quality Worst in ASEAN in 2022)