Enviro News Asia, Lumajang — The Bromo Tengger Semeru National Park Authority (BB TNBTS) released an official update regarding the intensified volcanic activity of Mount Semeru in Lumajang Regency, East Java. According to the Geological Agency’s Center for Volcanology and Geological Hazard Mitigation (PVMBG), the volcano experienced a rapid escalation in eruption activity accompanied by pyroclastic density currents (PDCs) on Wednesday, 19 November 2025.
Based on Special Report No. 145/GL.03/BGL/2025 issued by PVMBG, the alert level of Mount Semeru was raised from Level II (Waspada) to Level III (Siaga) at 16:00 WIB, and subsequently upgraded to the highest alert level, Level IV (Awas), at 17:00 WIB. In response, BB TNBTS issued Announcement No. PG.17/T.8/TU/HMS.01.08/B/11/2025, declaring the temporary closure of all climbing activities on Mount Semeru, including access to Ranu Kumbolo.
At the time of the eruption, 187 climbers were present at Ranu Kumbolo, located 6.4 kilometers north of Mount Semeru’s summit—an area at risk of exposure to volcanic projectiles. Despite the elevated status, conditions at Ranu Kumbolo remained safe, as pyroclastic flows and lava avalanches moved toward the south–southeast, away from the lake area. Considering heavy rain, poor visibility, and evening conditions, authorities instructed climbers to remain in place overnight.
Evacuation commenced on Thursday, 20 November 2025. The first group reached Ranupani at 11:45 WIB, and the last group arrived safely at 14:30 WIB. All 187 climbers were accounted for and reported to be in good health upon arrival.
Given that Mount Semeru remains at Level IV (Awas), BB TNBTS urges the public, climbers, and tourism operators to strictly comply with all hazard-zone recommendations issued by PVMBG. Adherence to official instructions is essential to minimize risk amid ongoing volcanic instability.
BB TNBTS reaffirmed its commitment to providing transparent and continuous updates on the situation. The agency expressed appreciation for the cooperation of local communities and all parties involved in supporting emergency response and monitoring efforts. Authorities remain hopeful that conditions will stabilize soon, allowing tourism activities to resume safely and orderly. (*)
