Eruption at Semeru volcano ejects ash to 4 300 m (14 100 feet) a.s.l., Indonesia

Volcanic ash from Semeru in Indonesia was observed at 4 300 m (14 100 feet) above sea level at 21:10 UTC on November 3, 2025. The advisory was issued by the Darwin VAAC at 21:30 UTC on the same day.

Ash cloud height was reported at flight level 140, approximately 4 300 m (14 100 feet), moving southeast at 19 km/h (12 mph). Satellite imagery (Himawari-8) could not confirm the ash due to meteorological cloud cover; ash movement and height are based on ground observations and modeling. The current Aviation Color Code is Orange.

According to the Global Volcanism Program’s most recent report for September 24–30, 2025, Semeru exhibited daily eruptive events, with white-and-gray or gray ash plumes rising 400–900 m above the summit and drifting in various directions. The Alert Level was at 2, and the public was advised to stay at least 3 km from the summit and 8 km to the southeast due to ongoing hazards.

Semeru is an active stratovolcano located in East Java, Indonesia. Known hazards include ashfall, pyroclastic flows, lava flows, and lahars. The nearest significant population center is the city of Lumajang, which lies about 30 km (19 miles) to the southeast of the volcano, with smaller villages on nearby flanks at greater risk during eruptive episodes.