Warning! Mount Semeru Erupts Again This Afternoon (Thursday, September 25, 2025)

Mount Semeru in East Java erupted again on Thursday (25/9/2025) at 12:15 PM WIB. In the last week, Mount Semeru has erupted 20 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.

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

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

According to MAGMA Indonesia''s volcano activity report, Mount Semeru''s activity level is at Level II (Alert). Seismicity observations on September 25, 2025, from 00:00-23:59 WIB showed 74 eruption tremors with amplitudes of 10-22 millimeters and a tremor duration of 56-176 seconds.

Subsequently, 5 avalanche tremors with amplitudes of 2-3 mm and a tremor duration of 34-102 seconds, and 10 emission tremors with amplitudes of 3-8 millimeters and a tremor duration of 19-98 seconds occurred.

PVMBG urges against any activity in the southeast sector along Besuk Kobokan, as far as 8 kilometers from the peak (eruption center). Beyond this distance, the public 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 lahars up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,323 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 2,486 occurrences.

(Read: Chad Becomes Country with Worst Air Quality in the World 2024)