Mount Semeru Eruption Three Times, Eruption High Reaches 800 Meters

Mount Semeru erupted again with an eruption as high as 800 meters above the peak on Tuesday (4/11/2025). BETWEEN/HO-PVMBG

Mount Semeru, which is on the border of Lumajang and Malang Regencies, East Java, has erupted three times again with an eruption height of up to 800 meters above the peak.

"There was an eruption of Mount Semeru at 16.53 WIB with an eruption column height of about 800 meters above the peak or 4,476 meters above sea level (masl)," said Mount Semeru Observation Post Officer Yadi Yuliandi in a written report reported by ANTARA, Tuesday, November 4.

The ash column was observed to be gray with thick intensity to the north and the eruption was recorded on a seismograph with a maximum amplitude of 22 mm and a duration of 120 seconds.

Previously, the highest mountain on the island of Java had erupted twice at 07.14 WIB with an eruptive column height observed about 800 meters above the peak and at 15.52 WIB with an eruptive column height observed about 500 meters above the peak.

"The ash column was observed to be gray with thick intensity to the north. This eruption was recorded on a seismograph with a maximum amplitude of 22 mm and a duration of 150 seconds," he said.

He explained that Mount Semeru is still on Alert or Level II status, so that the Center for Volcanology and Geological Hazard Mitigation (PVMBG) provides a number of recommendations, namely that people are prohibited from carrying out any activity in the southeast sector, along Besuk Kobokan as far as eight kilometers from the summit (the center of the eruption).

Outside of that distance, he said, people are not allowed to carry out activities at a distance of 500 meters from the riverbank along Besuk Kobokan, because it has the potential to be affected by the expansion of hot clouds and lava flows up to a distance of 13 kilometers from the summit.

"People are also advised not to move within a three-kilometer radius of the crater or peak of Mount Semeru, because it is prone to the dangers of incandescent stones," he said.

He appealed to the public to be aware of the potential for hot clouds, lava avalanches, and rain lava along rivers/valleys whose water flows originate at the top 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 from Besuk Kobokan.