Volcanic ash from Lewotobi volcano observed at 5 500 m (18 000 feet) a.s.l., Indonesia

Volcanic ash from Lewotobi in Indonesia was observed at 5 500 m (18 000 feet) above sea level at 21:40 UTC on October 14, 2025. The advisory was issued by the Darwin VAAC at 22:00 UTC on October 14, 2025.

The ash cloud was discernible in the latest Himawari-8 satellite imagery. Ash was observed at the surface up to flight level 180 (approximately 5 500 m or 18 000 feet), moving west-northwest in light winds. The advisory noted that volcanic ash lingering near the summit in light winds was expected to dissipate over the next 6 hours. The current Aviation Color Code is Red. Forecasts indicated that ash could rise up to flight level 220 (about 6 700 m or 22 000 feet) in the next 18 hours.

According to the Smithsonian / USGS Weekly Volcanic Activity Report for September 24–30, 2025, Lewotobi Laki-laki produced daily white-and-gray ash plumes rising up to 2 000 m (6 600 feet) above the summit and drifting north, northwest, west, and southwest. Significant seismic activity and eruptive events were observed, and the public was advised to remain 6 km (3.7 miles) from the summit as of September 29, 2025.

Lewotobi is a twin stratovolcano complex in eastern Flores, Indonesia, consisting of Lewotobi Laki-laki and Lewotobi Perempuan cones. The volcano is known for producing ash plumes and occasional explosive eruptions, with hazards including ashfall, pyroclastic flows, and lava flows. Surrounding rural communities and the regional town of Larantuka, located approximately 50 km (31 miles) northeast, may be at risk during larger eruptive episodes.