Mount Semeru Erupts Again Tonight (Monday, January 12, 2026)

Mount Semeru in East Java erupted again on Monday (1/12/2026) at 09:45 PM WIB. In the last week, Mount Semeru has erupted 10 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 be around None meters above the peak or None meters above sea level.

The visual eruption was not observed. Mount Semeru's eruption is still ongoing as this report was made.

(Read: 4.7 M Earthquake Shakes Bonin Islands, Region)

According to MAGMA Indonesia's volcanic activity report, Mount Semeru's activity level is at Level III (Alert). Seismic observations on January 12, 2026, from 12:00-18:00 WIB showed 36 eruption earthquakes with amplitudes of 10-22 millimeters and durations of 75-196 seconds.

Subsequently, there were 3 harmonic tremors with amplitudes of 1-2 millimeters and durations of 351-512 seconds, and 1 local tectonic earthquake with an amplitude of 15 millimeters, S-P time of 9 seconds, and a duration of 29 seconds.

PVMBG urges against any activity in the southeast sector along Besuk Kobokan, up to 13 kilometers from the peak (eruption center). Beyond that distance, people should not engage in activities within 500 meters of the river banks (riverine borders) along Besuk Kobokan as there is a potential for expansion of hot clouds and lava flows up to 17 kilometers from the peak.

Throughout 2026, MAGMA Indonesia has recorded 178 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 99 events.

(Read: 4.5 M Earthquake Shakes 94 Km Southwest of Banda Aceh,)