Alert! Mount Semeru Erupts Again This Morning (Saturday, April 18, 2026)

Mount Semeru in East Java erupted again on Saturday (April 18, 2026) at 07:24 WIB. In the past week, Mount Semeru has erupted 49 times.

Based on eruption information from the Center for Volcanology and Geological Hazard Mitigation (PVMBG) via the MAGMA Indonesia application, the observed ash column height is around 800 meters above the peak (4,476 meters above sea level).

The ash column was observed to be white to gray with thick intensity towards the southwest. The eruption was recorded on the seismograph with a maximum amplitude of 22 millimeters and a duration of 130 seconds.

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According to the MAGMA Indonesia volcanic activity report, the activity level of Mount Semeru is at Level III (Alert). Earthquake observations on April 18, 2026, from 00:00 to 06:00 WIB showed 11 eruption/explosion earthquakes with amplitudes of 11-22 millimeters and durations of 94-152 seconds.

Then, 1 emission earthquake with an amplitude of 6 millimeters and a duration of 32 seconds, as well as 1 harmonic earthquake with an amplitude of 7 millimeters and a duration of 214 seconds.

PVMBG advises against any activities in the southeast sector along the Besuk Kobokan, within 13 kilometers of the peak (eruption center). Beyond this distance, residents are advised not to carry out activities within 500 meters of the riverbank along the Besuk Kobokan due to the potential for being affected by expanding hot clouds and lava flows up to 17 kilometers from the peak.

In 2026, MAGMA Indonesia has recorded 1,542 volcanic eruptions across Indonesia. Mount Semeru in East Java has the most eruptions with 824 events.

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