Mount Semeru Erupts Five Times in a Row, Eruption Height Reaches 700 Meters

Volcanic activity at Mount Semeru, located on the border of Lumajang and Malang regencies, East Java, has shown another increase. On Monday (3/8/2026) morning, the tallest mountain on Java Island was reported to have experienced five consecutive eruptions with ash columns ranging from 300 to 700 meters above the peak.

This series of eruptions began in the early hours at 00:18 WIB with an observed ash column height of approximately 500 meters, drifting toward the north. A few minutes later, at 00:31 WIB, Semeru erupted again with the ash column reaching 700 meters above the peak.

The third eruption was then detected at 01:46 WIB with a 600-meter-high ash plume, also moving north. Entering the morning at 05:50 WIB, a fourth eruption occurred with an ash column 300 meters high drifting southwest.

The fifth eruption, which was observed to be quite significant, occurred at 07:56 WIB with a thick ash column reaching 700 meters moving southeast. According to seismograph records, this latest eruption was recorded with a maximum amplitude of 22 mm and an earthquake duration of 120 seconds.

Mount Semeru Observation Post officer, Liswanto, stated that the level of volcanic activity for Semeru currently remains at Alert Level III (Siaga). Authorities recommend that the public refrain from any activities in the southeastern sector along Besuk Kobokan up to a 13-kilometer radius from the eruption center.

Beyond that safe distance, residents are also prohibited from conducting activities within a 500-meter radius of the riverbanks along Besuk Kobokan due to the potential threat of lahar flows and pyroclastic surge expansion up to 17 kilometers from the peak. Additionally, a sterile zone within a 5-kilometer radius of the active crater must be observed to avoid the danger of flying incandescent rocks.

The local government urges the public to remain calm yet vigilant against potential pyroclastic flows, lava flows, and cold lahar floods along the riverbeds originating from the peak of Semeru, such as Besuk Kobokan, Besuk Bang, Besuk Kembar, and Besuk Sat.