Mount Semeru Erupts Again Tonight (Friday, September 5, 2025)

Mount Semeru in East Java erupted again on Friday (September 5, 2025) at 00:01 WIB. In the last week, Mount Semeru has erupted 20 times.

Citing 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.

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

(Read: Countries with the Most Active Volcanoes in the World, Indonesia Ranks First)

According to MAGMA Indonesia''s volcanic activity report, Mount Semeru''s activity level is at Level II (Alert). Seismicity observations on September 5, 2025, from 00:00-23:59 WIB showed 45 eruption/explosion earthquakes with amplitudes of 10-22 millimeters and earthquake durations of 50-179 seconds.

Subsequently, there were 2 rockfall earthquakes with amplitudes of 6-10 mm and durations of 63-80 seconds, and 2 exhalation earthquakes with an amplitude of 8 millimeters and durations of 53-55 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 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 5,964 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most with 2,388 occurrences.

(Read: Volcanic Eruption Trends in Recent Years)