Warning! Mount Semeru Erupts Again This Morning (Tuesday, August 12, 2025)

Mount Semeru in East Java erupted again on Tuesday (12/8/2025) at 10:03 AM WIB. In the last week, Mount Semeru has erupted 14 times.

Based on eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the observed ash column height reached None meters above the peak or None meters above sea level.

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

(Read: The Impact of Natural Disaster Damage from January-March 2023)

According to MAGMA Indonesia's volcano activity report, Mount Semeru's activity level is at Level II (Alert). Seismic observations on August 12, 2025, from 00:00-23:59 WIB showed 47 eruption earthquakes with amplitudes of 10-22 millimeters and earthquake durations of 50-248 seconds.

Subsequently, there were 14 exhalation earthquakes with amplitudes of 4-8 millimeters and durations of 39-105 seconds, and 4 harmonic earthquakes with amplitudes of 3-8 millimeters and durations of 104-234 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 is advised not to 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 5,576 volcano eruptions across Indonesia. Mount Semeru in East Java has erupted the most with 2,231 times.

(Read: The Most Frequent Natural Disasters in Indonesia Until Early September 2023)