Mount Semeru Erupts Again This Afternoon (Wednesday, December 10, 2025)

Mount Semeru in East Java erupted again on Wednesday (10/12/2025) at 12:24 PM WIB. In the last week, Mount Semeru has erupted 14 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 approximately None meters above the peak (None meters above sea level).

Visual eruption was not observed. The eruption of Mount Semeru was still ongoing when this report was made.

(Read: Majority of Indonesians Access Air Quality Information from Social Media)

According to MAGMA Indonesia's volcanic activity report, Mount Semeru's activity level is at Level III (Alert). Seismic observations on December 10, 2025, from 06:00-12:00 WIB showed 42 eruption tremors with amplitudes of 10-22 millimeters and a duration of 64-128 seconds. Additionally, there were 4 exhalation tremors with amplitudes of 6-8 millimeters and a duration of 33-86 seconds.

PVMBG advises against any activities in the southeast sector along Besuk Kobokan, up to 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 due to the potential for expansion of hot clouds and lava flows up to 17 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 7,279 volcanic eruptions across Indonesia. Mount Semeru in East Java has erupted the most, with 2,992 eruptions.

(Read: Not Jakarta, This is the Region with the Worst Air Quality in Indonesia (Wednesday, June 7, 2023))