Mount Semeru Erupts Again Tonight (Sunday, October 19, 2025)

Mount Semeru in East Java erupted again on Sunday (19/10/2025) at 21:43 WIB. In the last week, Mount Semeru has erupted 26 times.

According to eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the height of the observed ash column reached 700 meters above the peak (4,376 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 22 millimeters and a duration of 158 seconds.

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According to MAGMA Indonesia's volcano activity report, Mount Semeru's activity level is at Level II (Alert). Seismicity observations on October 19, 2025, from 00:00-23:59 WIB, showed 54 eruption earthquakes with amplitudes of 10-22 millimeters and durations of 62-158 seconds.

Furthermore, there were 12 avalanche earthquakes with amplitudes of 2-4 mm and durations of 37-137 seconds, and 21 emission earthquakes with amplitudes of 3-8 millimeters and durations of 49-86 seconds.

PVMBG advises 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 is advised not to engage in activities within 500 meters from the riverbanks along Besuk Kobokan, as there is a potential for expansion of hot clouds and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,711 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 2,639 events.

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