Mount Semeru Erupts Again Tonight (Wednesday, January 7, 2026)

Mount Semeru in East Java erupted again on Wednesday (January 7, 2026) at 18:12 WIB. In the last week, Mount Semeru has erupted 23 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 approximately 800 meters above the peak (4,476 meters above sea level).

The ash column was observed to be white to gray with moderate intensity towards the north. The eruption of Mount Semeru was still ongoing when this report was made.

(Read: Volcanic Eruption Trends in Recent Years)

According to MAGMA Indonesia's volcanic activity report, the activity level of Mount Semeru is at Level III (Alert). Seismic observations on January 7, 2026, from 12:00-18:00 WIB showed 22 eruption/explosion earthquakes with amplitudes of 11-22 millimeters and durations of 65-108 seconds.

Furthermore, there were 7 exhalation earthquakes with amplitudes of 4-7 millimeters and durations of 40-72 seconds, and 1 harmonic earthquake with an amplitude of 2 millimeters and a duration of 181 seconds.

PVMBG advises against any activities in the southeast sector along Besuk Kobokan, as far as 13 kilometers from the peak (eruption center). Beyond this distance, the public is advised not to conduct activities within 500 meters from the riverbanks (river borders) along Besuk Kobokan, as there is potential for expansion of hot clouds and lava flows up to 17 kilometers from the peak.

Throughout 2026, MAGMA Indonesia has recorded 103 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions with 60 occurrences.

(Read: Indonesia Has the Most Active Volcanoes in the World)