Warning! Mount Semeru Erupts Again Tonight (Sunday, January 18, 2026)

Mount Semeru in East Java erupted again on Sunday (1/18/2026) at 23:49 WIB. In the last week, Mount Semeru has erupted 57 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 was observed to be around 500 meters above the peak or 4,176 meters above sea level.

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

(Read: Countries with the Most Active Volcanoes in the World, Indonesia Ranks First)

According to the MAGMA Indonesia volcano activity report, the activity level of Mount Semeru is at Level III (Alert). Seismic observations on January 18, 2026, from 12:00-18:00 WIB showed 27 eruption earthquakes with amplitudes of 15-22 millimeters and durations of 69-129 seconds.

Additionally, there were 4 gas emission earthquakes with amplitudes of 4-5 millimeters and durations of 42-83 seconds, and 1 distant tectonic earthquake with an amplitude of 35 millimeters s-p 13 seconds and a duration of 40 seconds.

PVMBG urges against any activity in the southeastern sector along Besuk Kobokan, 13 kilometers from the peak (eruption center). Beyond this distance, the public is advised not to engage in activities within 500 meters from the riverbanks (river borders) along Besuk Kobokan due to the potential for expansion of hot clouds and lahars up to 17 kilometers from the peak.

Throughout 2026, MAGMA Indonesia has recorded 259 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 146 occurrences.

(Read: Volcanic Eruption Trends in Recent Years)