Mount Semeru Erupts Again Tonight (Thursday, October 23, 2025)

Mount Semeru in East Java erupted again on Thursday (23/10/2025) at 22:59 WIB. In the last week, Mount Semeru has erupted 32 times.

Citing 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 reach 400 meters above the peak or 4,076 meters above sea level.

The ash column was observed to be white to gray with thick intensity towards the southwest. The eruption was recorded on a seismograph with a maximum amplitude of 12 millimeters and a duration of 97 seconds.

(Read: Concession Areas in Peat Ecosystems Prone to Flooding, Especially Palm Oil Concessions)

According to the MAGMA Indonesia volcano activity report, Mount Semeru's activity level is at Level II (Alert). Seismic observations on October 23, 2025, from 00:00-23:59 WIB showed 63 eruption/explosion earthquakes with amplitudes of 10-22 millimeters and durations of 51-152 seconds.

Subsequently, 5 times avalanche earthquakes with amplitudes of 3-4 mm and durations of 38-82 seconds, and 13 times gas emission earthquakes with amplitudes of 3-8 millimeters and durations of 28-58 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 is advised not to engage in activities within 500 meters from the riverbanks (river borders) along Besuk Kobokan as there is potential for expansion of hot clouds and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,762 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most with 2,672 eruptions.

(Read: Bekasi Among 10 Areas with Highest Flood Risk in West Java)