Warning! Mount Semeru Erupts Again Tonight (Saturday, January 31, 2026)

Mount Semeru in East Java erupted again on Saturday (January 31, 2026) at 00:21 WIB. In the last week, Mount Semeru has erupted 28 times.

Based on eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the height of the observed ash column was approximately 700 meters above the peak (4,376 meters above sea level).

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

(Read: There Were 137 Natural Disaster Events Nearing the End of January 2024, Floods Were the Most Frequent)

According to MAGMA Indonesia's volcanic activity report, Mount Semeru's activity level is at Level III (Alert). Seismic observations on January 31, 2026, from 18:00-23:59 WIB, showed 21 eruption/emission earthquakes with amplitudes of 11-23 millimeters and durations of 69-129 seconds.

Additionally, there was 1 rockfall earthquake with an amplitude of 9 mm and a duration of 119 seconds, and 7 gas emission earthquakes with amplitudes of 2-7 millimeters and durations of 44-67 seconds.

PVMBG advises against any activity 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 of the riverbank (river border) along Besuk Kobokan, as there is a potential for hot cloud expansion and lahars to reach up to 17 kilometers from the peak.

Throughout 2026, MAGMA Indonesia has recorded 404 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 210 events.

(Read: Number of Natural Disaster Fatalities in Indonesia Surged in 2024)