Mount Semeru Erupts Again This Afternoon (Monday, August 18, 2025)

Mount Semeru in East Java erupted again on Monday (August 18, 2025) at 11:40 AM WIB. In the last week, Mount Semeru has only erupted once.

According to eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the height of the observed ash column reached None meters above the peak (None meters above sea level).

No visual eruption was observed. The eruption was recorded on a seismograph with a maximum amplitude of 22 millimeters and a duration of 122 seconds.

(Read: Forest and Land Fire Hotspots in South Sumatra Increased in Mid-October 2023)

According to the MAGMA Indonesia volcano activity report, Mount Semeru's activity level is at Level II (Alert). Seismic observations on August 18, 2025, from 00:00-23:59 WIB showed 45 eruption/explosion earthquakes with amplitudes of 11-22 millimeters and durations of 36-221 seconds.

Additionally, there were 4 avalanche earthquakes with amplitudes of 4-6 mm and durations of 43-81 seconds, and 8 puff earthquakes with amplitudes of 3-6 millimeters and durations of 31-53 seconds.

PVMBG advises against any activities in the southeast sector along Besuk Kobokan, as far as 8 kilometers from the peak (eruption center). Beyond this distance, the public should not conduct 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 13 kilometers from the peak.

Throughout 2025, MAGMA Indonesia has recorded 5,674 volcanic eruptions/outbreaks across Indonesia. Mount Semeru in East Java has erupted the most with 2,276 occurrences.

(Read: Indication of Forest and Land Fire Area in East Kalimantan until June 2025)