Volcanic ash from Marapi volcano observed at 4 300 m (14 100 feet) a.s.l., Indonesia

Volcanic ash from Marapi volcano in Indonesia was observed at 4 300 m (14 100 feet) above sea level at 19:50 UTC on October 8, 2025. The advisory was issued by the Darwin VAAC at 20:24 UTC on October 8, 2025.

According to the advisory, ash was detected at surface level up to flight level 140, which is approximately 4 300 m (14 100 feet) above sea level. The ash cloud was moving east at approximately 19 km/h (12 mph). The ash was identifiable on Himawari-9 satellite imagery, with height and movement based on ground reports, satellite data, and model information. The ash is forecast to dissipate within 6 hours. The current Aviation Color Code is Orange.

According to the Smithsonian / USGS Weekly Volcanic Activity Report for September 24–30, 2025, eruptive activity at Marapi continued, with eruptions recorded though weather conditions prevented visual confirmation of some events. On September 26, a dense white-and-gray ash plume rose 1 000 m (3 300 feet) above the summit and drifted east. The Alert Level remained at 2, and the public was advised to stay 3 km (1.9 miles) away from the active crater.

Marapi is a stratovolcano located in West Sumatra, Indonesia. The volcano is known for frequent ash-producing eruptions and is considered one of Sumatra’s most active volcanoes. Hazards include ashfall, pyroclastic flows, and lahars, which may affect communities within several kilometers (miles) of the summit, including the nearby town of Bukittinggi. Continued vigilance is needed for populations living within the hazard zone.