Warning! Mount Semeru Erupts Again Tonight (Saturday, October 18, 2025)

Mount Semeru in East Java erupted again on Saturday (18/10/2025) at 19:51 WIB. In the last week, Mount Semeru has erupted 23 times.

According to 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.

The eruption visual was not observed. The eruption was recorded on a seismograph with a maximum amplitude of 21 millimeters and a duration of 117 seconds.

(Read: Jakarta's Air Quality is Bad, Worse Than Other ASEAN Capitals)

According to MAGMA Indonesia's volcano activity report, Mount Semeru's activity level is at Level II (Alert). Seismic observations on October 18, 2025, from 00:00-23:59 WIB showed 63 eruption tremors with amplitudes of 10-22 millimeters and durations of 55-159 seconds.

Additionally, there were 2 avalanche tremors with amplitudes of 2-7 mm and durations of 83-117 seconds, and 22 gas emission tremors with amplitudes of 3-8 millimeters and durations of 33-76 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, people should not conduct activities within 500 meters from the riverbanks (river boundaries) 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 6,699 volcano eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 2,636 events.

(Read: Warning, Jakarta's Air Quality This Morning is the World's Worst (Thursday, June 15, 2023))