Mount Semeru Erupts Again Tonight (Friday, September 26, 2025)

Mount Semeru in East Java erupted again on Friday (September 26, 2025) at 6:13 PM WIB. In the last week, Mount Semeru has erupted 34 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 was observed to be around None meters above the peak or None meters above sea level.

No visual eruption was observed. Mount Semeru's eruption was still ongoing when this report was made.

(Read: Despite Rain, Jakarta's Air Quality Remains Poor)

According to MAGMA Indonesia's volcanic activity report, Mount Semeru's activity level is at Level II (Alert). Seismicity observations on September 26, 2025, from 00:00-23:59 WIB showed 85 eruption/explosion earthquakes with amplitudes of 10-22 millimeters and earthquake durations of 51-192 seconds.

Furthermore, 12 exhalation earthquakes with amplitudes of 4-8 millimeters and durations of 43-80 seconds, and 5 harmonic tremors with amplitudes of 2-8 millimeters and durations of 43-80 seconds occurred.

PVMBG advises against 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 (river borders) along Besuk Kobokan due to the potential for hot cloud expansion and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,358 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most with 2,500 times.

(Read: Indonesia, the Country with the Worst Air Quality in Southeast Asia)