Volcanic activity at Mount Semeru increased again on Friday (19/6/2026) morning. The highest mountain on Java Island, located on the border of Lumajang and Malang Regencies, was observed spewing pyroclastic density currents (pyroclastic flows) reaching a distance of 4.5 kilometers.
An officer at the Mount Semeru Observation Post, Mukdas Sofian, reported that the eruption occurred at precisely 07:21 WIB. A thick column of white-to-gray ash was observed rising 1,000 meters above the peak, or approximately 4,676 meters above sea level, drifting toward the north and northwest.
Seismogram data recorded the eruption with a maximum amplitude of 22 millimeters and an activity duration of five minutes and 33 seconds. This phenomenon was recorded as one of six eruptions during that period, with column heights varying between 700 and 1,000 meters.
Currently, Mount Semeru remains at Level III (Alert) status. Relevant authorities emphasized a strict ban on residents conducting activities in the southeastern sector along Besuk Kobokan within a 13-kilometer radius from the eruption center. Additionally, the public is advised not to carry out activities within a 5-kilometer radius of the main crater to avoid the danger of incandescent rock projectiles.
Residents living along river basins originating from the mountain peak, such as Besuk Bang, Besuk Kembar, and Besuk Sat, are urged to remain vigilant against threats of pyroclastic flows, lava avalanches, and cold lahar floods that could occur at any time due to extreme weather at the summit.
