Ash emissions from Semeru volcano reach 4 300 m (14 100 feet) a.s.l., Indonesia

Volcanic ash from Semeru in Indonesia was observed at an altitude of 4 300 m (14 100 feet) above sea level at 03:40 UTC on October 14, 2025. The advisory was issued by the Darwin VAAC at 04:00 UTC on the same day.

Ash was reported to reach up to flight level 140, which corresponds to approximately 4 300 m (14 100 feet). The ash plume was moving toward the northwest at around 9 km/h (6 mph). Ash was not identifiable in satellite imagery due to meteorological cloud cover, but ground reports confirmed intermittent discrete eruptions continuing. The current Aviation Color Code is Orange.

According to the latest Global Volcanism Program weekly report, Semeru continued to produce daily eruptive events during late September 2025, with white-and-gray or gray ash plumes rising 400–900 m (1 300–3 000 feet) above the summit and drifting in multiple directions. The Alert Level remained at 2, and the public was advised to stay at least 3 km (1.9 miles) away from the summit.

Semeru is a stratovolcano and the highest mountain on the island of Java. It poses significant hazards such as ashfall, pyroclastic flows, lahars, and lava avalanches. Settlements near the volcano, including the town of Lumajang approximately 18 km (11 miles) to the southeast, may be at risk from these hazards.