Mount Semeru Erupts and Spews Hot Clouds on Saturday Night

Mount Semeru experienced an eruption accompanied by pyroclastic flows on Saturday (16/5) evening. The mountain is located on the border between Lumajang and Malang regencies, East Java.

“An eruption of Mount Semeru occurred at 7:04 PM local time, with the height of the eruption column observed to be about 1,000 meters above the summit or 4,676 meters above sea level,” said Officer at the Semeru Volcano Observation Post, Mukdas Sofian, in a written report received in Lumajang, as reported by Antara on Saturday (16/5).

The ash column was observed to be white to grey with thick intensity, heading towards the southwest.

The eruption was also recorded on the seismograph with a maximum amplitude of 22 mm and a duration of about 5 minutes and 16 seconds.

“The eruption was accompanied by pyroclastic flows, but the distance traveled could not be observed because the slopes of Mount Semeru were covered in fog,” he said.

Then, the highest mountain on Java Island erupted again at 8:30 PM local time, with the height of the eruption column unobserved, but the eruption was recorded on the seismograph with a maximum amplitude of 22 mm and a duration of 171 seconds.

Mukdas explained that currently, the volcanic activity of Mount Semeru is at Level III (Alert) status, with a recommendation that people should not carry out any activities in the southeast sector along Besuk Kobokan, within a radius of 13 km from the summit (the center of the eruption).

“Outside this distance, people are prohibited from carrying out activities within a radius of 500 meters from the banks of the river (riverbanks) along Besuk Kobokan because they have the potential to be affected by the expansion of hot clouds and lava flows up to a distance of 17 km from the summit,” he said.

He also urged people not to carry out activities within a radius of 5 km from the crater/summit of Mount Semeru because they are at risk of being hit by falling rocks (pyroclastic material).

Furthermore, people are asked to be aware of the potential for hot clouds, lava flows, and lahars along river streams/valleys that originate at the summit of Mount Semeru.

“Especially along Besuk Kobokan, Besuk Bang, Besuk Kembar, and Besuk Sat, as well as the potential for lahars in small rivers that are tributaries of Besuk Kobokan,” he said.