Mount Semeru Erupts Again This Afternoon (Wednesday, September 3, 2025)

Mount Semeru in East Java erupted again on Wednesday (9/3/2025) at 12:26 PM WIB. In the last week, Mount Semeru has erupted 12 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 (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 110 seconds.

(Read: Indonesia Has the Most Active Volcanoes in the World)

According to MAGMA Indonesia''s volcanic activity report, Mount Semeru''s activity level is at Level II (Alert). Seismic observations on September 3, 2025, from 00:00-23:59 WIB showed 52 eruption earthquakes with amplitudes of 10-22 millimeters and durations of 42-238 seconds.

Furthermore, there were 2 rockfall earthquakes with amplitudes of 4-6 mm and durations of 64-113 seconds, and 6 emission earthquakes with amplitudes of 3-8 millimeters and durations of 41-76 seconds.

PVMBG advises against any activities in the southeastern sector along Besuk Kobokan, 8 kilometers from the peak (eruption center). Beyond that distance, people should not engage in activities within 500 meters from the riverbanks (river borders) along Besuk Kobokan due to the potential for expansion of hot clouds and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 5,943 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions with 2,380 events.

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