Mount Semeru Erupts, Hot Avalanche Cloud Travels 4.5 Kilometres

Mount Semeru, located on the border of Lumajang and Malang regencies in East Java, erupted on Friday morning, sending a hot avalanche cloud (APG) as far as 4.5 kilometres from its centre. According to Mukdas Sofian, an officer at the Mount Semeru Observation Post, the eruption occurred at 07:21 WIB, with the volcanic ash column observed reaching approximately 1,000 metres above the summit, or 4,676 metres above sea level. The ash column was white to grey in colour with thick intensity, drifting towards the north and northwest. The eruption was recorded on a seismograph with a maximum amplitude of 22 mm and a duration of roughly 5 minutes and 33 seconds.

Sofian stated that the eruption was accompanied by a hot avalanche cloud that travelled approximately 4.5 kilometres towards Besuk Kobokan. The volcano remains at Level III (Siaga) alert status. Under this status, the public is advised not to conduct any activities in the southeastern sector along Besuk Kobokan within a 13-kilometre radius from the summit, which is the eruption centre. Furthermore, residents are prohibited from engaging in activities within 500 metres of the riverbank along Besuk Kobokan, as there is a potential for the expansion of hot clouds and lahar flows reaching up to 17 kilometres from the peak.

The public is also urged to remain vigilant against the potential for hot clouds, lava avalanches, and lahars along river channels and valleys originating from the summit of Mount Semeru, particularly along Besuk Kobokan, Besuk Bang, Besuk Kembar, and Besuk Sat, as well as smaller tributaries of Besuk Kobokan.