Mount Semeru Erupts Again This Morning (Monday, August 11, 2025)

Mount Semeru in East Java erupted again on Monday (August 11, 2025) at 08:38 AM WIB. In the last week, Mount Semeru has erupted 2 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 700 meters above the peak (4,376 meters above sea level).

The ash column was observed to be gray with moderate intensity to the west. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 126 seconds.

(Read: Majority of Villages in IKN Area at Risk of Flooding)

According to the MAGMA Indonesia volcano activity report, the activity level of Mount Semeru is at Level II (Alert). Seismic observations on August 11, 2025, from 00:00-23:59 WIB showed 44 eruption earthquakes with amplitudes of 10-22 millimeters and a duration of 57-202 seconds.

In addition, there was 1 rockfall earthquake with an amplitude of 4 mm and a duration of 74 seconds, and 18 gas emission earthquakes with amplitudes of 4-8 millimeters and a duration of 32-84 seconds.

PVMBG urges 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 riverbank (river border) 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 5,557 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most, with 2,219 eruptions.

(Read: These are the Provinces Most Affected by Floods in Early 2025)