Mount Semeru Erupts Again This Morning (Monday, September 15, 2025)

Mount Semeru in East Java erupted again on Monday (September 15, 2025) at 05:12 AM WIB. In the last week, Mount Semeru has erupted twice.

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 (None meters above sea level).

The visual eruption was not observed. Mount Semeru''s eruption was still ongoing when this report was made.

(Read: Indonesia Becomes the Most Earthquake-Prone Country as of 2025)

According to MAGMA Indonesia''s volcano activity report, Mount Semeru''s activity level is at Level II (Alert). Seismicity observations on September 15, 2025, from 00:00-23:59 WIB showed 53 eruption tremors with amplitudes of 10-22 millimeters and a duration of 54-221 seconds.

Subsequently, there were 2 rockfall tremors with amplitudes of 4-6 mm and a duration of 55-66 seconds, and 2 exhalation tremors with an amplitude of 6 millimeters and a duration of 32-65 seconds.

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, as there is a potential for hot cloud expansion and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,103 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most with 2,449 occurrences.

(Read: A 4.5 M Earthquake Shakes 94 Km Southwest of Banda Aceh,)