Mount Semeru Erupts Again This Morning (Friday, October 3, 2025)

Mount Semeru in East Java erupted again on Friday (October 3, 2025) at 10:54 AM WIB. In the last week, Mount Semeru has erupted 27 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 600 meters above the peak (4,276 meters above sea level).

The ash column was observed to be white to grey with thick intensity towards the southwest. The eruption was recorded on a seismograph with a maximum amplitude of 23 millimeters and a duration of 105 seconds.

(Read: Trends in Volcanic Eruptions in Recent Years)

According to MAGMA Indonesia's volcano activity report, Mount Semeru's activity level is at Level II (Alert). Seismic observations on October 3, 2025, from 00:00-23:59 WIB showed 92 eruption earthquakes with amplitudes of 10-22 millimeters and earthquake durations of 69-204 seconds.

Furthermore, 1 rockfall earthquake with an amplitude of 8 mm and an earthquake duration of 90 seconds, and 11 emission earthquakes with amplitudes of 3-8 millimeters and earthquake durations of 34-65 seconds occurred.

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 should not engage in activities within 500 meters from the riverbanks (river boundaries) along Besuk Kobokan, as there is a potential for expansion of pyroclastic clouds and lahar flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,515 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most, with 2,549 eruptions.

(Read: Indonesia Has the Most Active Volcanoes in the World)