Warning! Mount Semeru Erupts Again Tonight (Wednesday, August 20, 2025)

Mount Semeru in East Java erupted again on Wednesday (20/8/2025) at 00:33 WIB. In the last week, Mount Semeru has erupted 9 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 observed reached None meters above the peak or None meters above sea level.

The visual of the eruption was not observed. The eruption of Mount Semeru was still ongoing when this report was made.

(Read: West Kalimantan Produced the Most CO2 Emissions from Forest Fires Until July 2023)

According to the MAGMA Indonesia volcano activity report, the activity level of Mount Semeru is at Level II (Alert). Seismic observations on August 20, 2025, from 00:00-23:59 WIB showed 52 eruption/explosion earthquakes with amplitudes of 11-22 millimeters and earthquake durations of 41-238 seconds.

Then, 14 blast earthquakes with amplitudes of 3-9 millimeters and earthquake durations of 24-64 seconds, and 1 harmonic earthquake with an amplitude of 3 millimeters and an earthquake duration of 267 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, the public should not engage in activities within 500 meters from the riverbanks (river borders) along Besuk Kobokan due to the potential for hot cloud expansion and lava flows up to 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 5,701 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most, with 2,284 eruptions.

(Read: 55 Disasters Occurred in Mid-September 2023, Forest Fires Dominated)