Warning! Mount Semeru Erupts Again This Morning (Wednesday, September 24, 2025)

Mount Semeru in East Java erupted again on Wednesday (9/24/2025) at 05:50 AM WIB. In the last week, Mount Semeru has erupted 13 times.

Based on 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 400 meters above the peak or 4,076 meters above sea level.

The ash column was observed to be white to grey with thick intensity towards the southwest and west. The eruption was recorded on a seismograph with a maximum amplitude of 21 millimeters and a duration of 105 seconds.

(Read: Floods Dominate Natural Disasters in Indonesia in Early 2024)

According to MAGMA Indonesia''s volcano activity report, the activity level of Mount Semeru is at Level II (Alert). Seismic observations on September 24, 2025, from 00:00-23:59 WIB showed 71 eruption tremors/earthquakes with amplitudes of 10-22 millimeters and earthquake durations of 56-189 seconds.

Furthermore, there were 6 rockfall earthquakes with amplitudes of 2-3 mm and durations of 39-102 seconds, and 13 exhalation earthquakes with amplitudes of 3-8 millimeters and durations of 44-71 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 engage in activities within 500 meters from the riverbanks (river borders) along Besuk Kobokan due to the potential for being affected by the expansion of hot clouds and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 6,300 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most, with 2,479 times.

(Read: Hundreds of Natural Disasters Until Early April 2024, Floods Most Frequent)