Semeru Eruption with Eruption Height Reaching 600 Meters

Mount Semeru erupted with an eruption as high as 600 meters above the peak on Thursday (12/3/2026). ANTARA/HO-PVMBG

JAKARTA - Mount Semeru, which is on the border of Lumajang and Malang Regencies, East Java, has experienced four eruptions with an eruption height of 600 meters above the peak.

The first eruption occurred at 00.27 WIB with an unobservable eruption, and at 00.31 WIB there was another eruption with an unobservable eruption.

"Mount Semeru erupted again at 05.28 WIB with an observed eruption column height of about 600 meters above the peak or about 4,276 meters above sea level (msl)," said Mount Semeru Observation Post Officer Liswanto as reported by ANTARA, Thursday, March 12.

He said, the column of ash observed was white to gray with medium intensity towards the north.

Only 18 minutes later, the highest mountain on Java erupted for the fourth time at 05.46 WIB with an observed eruption column height of about 300 meters above the peak (3,976 m asl).

"The observed ash column is white to gray with medium intensity towards the north," he said.

Liswanto explained that Mount Semeru is in a Level III (Alert) volcanic activity status, so the Center for Volcanology and Geological Hazard Mitigation (PVMBG) has provided a number of recommendations, namely that the public should not carry out any activities in the southeast sector along Besuk Kobokan, as far as 13 kilometers from the peak (center of the eruption).

Outside this distance, he said, people should not carry out activities at a distance of 500 meters from the river bank (river border) along Besuk Kobokan because they have the potential to be hit by the expansion of the hot cloud and lava flow up to a distance of 17 kilometers from the peak.

"The public is also prohibited from carrying out activities within a radius of five kilometers from the crater/peak of Mount Semeru, because they are prone to the danger of stone throwing (pijar)," he said.

The public needs to be aware of the potential for hot clouds, lava ejection, and lahar along the river/valley streams upstream of the summit of Mount Semeru.

"Especially along Besuk Kobokan, Besuk Bang, Besuk Kembar, and Besuk Sat, as well as the potential for lava in small rivers which are tributaries of Besuk Kobokan," he said.