Warning! Mount Semeru Erupts Again This Afternoon (Friday, December 26, 2025)

Mount Semeru in East Java erupted again on Friday (26/12/2025) at 3:27 PM WIB. In the last week, Mount Semeru has erupted 35 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 900 meters above the peak or 4,576 meters above sea level.

The ash column was observed to be white to gray with thick intensity towards the northeast. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 108 seconds.

(Read: 295 People Died Due to Floods and Landslides in North Sumatra, Here's the Distribution (December 4, 2025))

According to MAGMA Indonesia's volcanic activity report, Mount Semeru's activity level is at Level III (Alert). Seismicity observations on December 26, 2025, from 06:00-12:00 WIB showed 33 eruption/explosion earthquakes with amplitudes of 10-22 millimeters and earthquake durations of 58-130 seconds.

Furthermore, there were 6 exhalation earthquakes with amplitudes of 3-8 millimeters and durations of 38-76 seconds, and 3 harmonic earthquakes with amplitudes of 1-3 millimeters and durations of 97-196 seconds.

PVMBG urges against any activity in the southeast sector along Besuk Kobokan, as far as 13 kilometers from the peak (eruption center). Beyond that distance, people should not engage in activities within 500 meters from the riverbanks (river 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 2025, MAGMA Indonesia has recorded 7,522 volcanic eruptions across Indonesia. Mount Semeru in East Java had the most eruptions, with 3,133 events.

(Read: Floods, the Most Frequent Disaster in Indonesia as of November 28, 2025)