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

Mount Semeru in East Java erupted again on Monday (9/29/2025) at 00:40 WIB. In the last week, Mount Semeru has erupted 2 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 or None meters above sea level.

Eruption visuals were not observed. Mount Semeru's eruption was still ongoing when this report was made.

(Read: There were 1.7 Thousand Natural Disasters in Indonesia until Early June 2023, Mostly Floods)

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/explosion earthquakes with amplitudes of 11-22 millimeters and earthquake durations of 47-138 seconds.

Subsequently, 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 activities in the southeast sector along Besuk Kobokan, 8 kilometers from the peak (eruption center). Beyond this distance, the public should not conduct activities within 500 meters from the riverbanks along Besuk Kobokan, as there is a potential for expansion of hot clouds and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,427 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 2,524 occurrences.

(Read: Climate Change-Related Natural Disasters Increase Globally)