Mount Semeru Erupts Again Tonight (Thursday, September 11, 2025)

Mount Semeru in East Java erupted again on Thursday (9/11/2025) at 18:29 WIB. In the last week, Mount Semeru has erupted 22 times.

Quoting 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 of the eruption was not observed. The eruption of Mount Semeru was still ongoing when this report was made.

(Read: These are the 10 Largest Earthquakes in History, Two of Them from Indonesia)

According to MAGMA Indonesia''s volcano activity report, Mount Semeru''s activity level is Level II (Alert). Seismic observations on September 11, 2025, from 00:00-23:59 WIB showed 46 eruption tremors with amplitudes of 10-22 millimeters and a duration of 54-183 seconds.

Then, 6 rockfall tremors with amplitudes of 3-10 mm and a duration of 45-172 seconds, and 10 exhalation tremors with amplitudes of 3-8 millimeters and a duration of 37-66 seconds.

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, the public is advised not to carry out activities within 500 meters from the river bank (river border) along Besuk Kobokan because it has the potential to be affected by the expansion of hot clouds and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,050 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most with 2,424 eruptions.

(Read: 4.8 M Earthquake Shakes 219 Km East of Levuka,)