Warning! Mount Semeru Erupts Again Tonight (Monday, January 5, 2026)

Mount Semeru in East Java erupted again on Monday (5/1/2026) at 22:58 WIB. In the last week, Mount Semeru only erupted once.

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 was observed to be approximately None meters above the peak (None meters above sea level).

The visual eruption was not observed. The eruption was recorded on a seismograph with a maximum amplitude of 23 millimeters and a duration of 143 seconds.

(Read: Despite the Rain, Jakarta's Air Quality Remains Poor)

According to MAGMA Indonesia's volcanic activity report, Mount Semeru's activity level is at Level III (Alert). Seismic observations on January 5, 2026, at 12:00-18:00 WIB showed 37 eruption tremors/eruptions with amplitudes of 10-22 millimeters and tremor durations of 64-114 seconds.

Subsequently, 1 rockfall tremor with an amplitude of 8 mm and a duration of 61 seconds, and 5 exhalation tremors with amplitudes of 2-8 millimeters and durations of 34-62 seconds occurred.

PVMBG urges against any activities in the southeast sector along Besuk Kobokan, as far as 13 kilometers from the peak (eruption center). Beyond that distance, people should not conduct activities within 500 meters from the riverbanks (river border) along Besuk Kobokan due to the potential for expansion of hot clouds and lava flows up to 17 kilometers from the peak.

Throughout 2026, MAGMA Indonesia has recorded 72 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 38 occurrences.

(Read: Air Quality in Indonesia Slightly Improved in 2021)