Mount Semeru showed significant volcanic activity again on Friday (19/6/2026) morning. At around 07:21 WIB, the tallest mountain on Java Island spewed pyroclastic density currents that traveled 4,500 meters from the eruption center. According to data from the Mount Semeru Observation Post, a thick ash column rose up to 1,000 meters above the peak, drifting toward the north and northwest.
The Center for Volcanology and Geological Hazard Mitigation (PVMBG) recorded the eruption on a seismograph with a maximum amplitude of 22 mm and a duration of 5 minutes and 33 seconds. As of now, Mount Semeru's status remains at Level III (Alert), indicating that volcanic activity levels remain above normal thresholds.
The Lumajang Regency Government, through the Regional Disaster Management Agency (BPBD), confirmed that the hot material flows have not reached residential areas. Nevertheless, local authorities continue to urge the public to exercise extra vigilance against potential follow-up pyroclastic flows and the threat of cold lava floods, especially during rain around the summit.
As a mitigation measure, PVMBG strictly prohibits any activity within a 13-kilometer radius in the southeastern sector along Besuk Kobokan. Additionally, residents are forbidden from approaching within 500 meters of the riverbanks in that area to avoid the risk of expanding pyroclastic flows, which could reach up to 17 kilometers.
On the other hand, the Bromo Tengger Semeru National Park Management (BB TNBTS) confirmed that the hiking trail to the summit of Semeru is completely closed. Tourists are only allowed to hike as far as the Ranu Kumbolo area. Meanwhile, tourism activities at Mount Bromo remain fully operational, as the volcanic systems of the two mountains are distinct and monitored separately.
