Volcanic ash from Lewotobi volcano observed at 6 700 m (22 000 feet) a.s.l., Indonesia

Volcanic ash from Lewotobi volcano in Indonesia was observed at 6 700 m (22 000 feet) above sea level at 12:00 UTC on October 15, 2025. The advisory was issued by VAAC Darwin at 12:20 UTC.

Ash was detected at two separate heights: one at 4 600 m (15 000 feet) and another at 6 700 m (22 000 feet), both moving to the north-northwest from the summit. The ash was confirmed via Himawari-8 satellite imagery and model guidance. The current Aviation Color Code is Red. Ash at 4 600 m (15 000 feet) is forecast to dissipate within 3 to 6 hours, while ash at 6 700 m (22 000 feet) is expected to dissipate within 12 hours.

According to the Smithsonian / USGS Weekly Volcanic Activity Report for late September 2025, Lewotobi Laki-laki produced daily white-and-gray or gray ash plumes reaching as high as 2 000 m (6 600 feet) above the summit and drifting in several directions. Seismic activity indicated eruptive events and emissions, and the alert level was recently lowered to 3, with a 6 km (3.7 miles) exclusion zone around the center.

Lewotobi is a stratovolcano located on Flores Island, Indonesia. It consists of twin volcanic cones known as Lewotobi Laki-laki and Lewotobi Perempuan. Typical hazards include ashfall, pyroclastic flows, and possible lava flows. The main population center at risk is the town of Larantuka, located approximately 60 km (37 miles) to the northeast, with other smaller settlements in closer proximity. Continued monitoring is recommended for nearby communities due to the potential for ongoing volcanic hazards.