Volcanic ash from Klyuchevskoy volcano observed at 7 300 m (24 000 feet) a.s.l., Russia

Volcanic ash from Klyuchevskoy in Russia was observed at 7 300 m (24 000 feet) above sea level at 19:10 UTC on October 16, 2025. The advisory was issued by Tokyo VAAC at 19:34 UTC.

According to the VAAC advisory, ash was observed at flight level 240, which corresponds to approximately 7 300 m (24 000 feet) a.s.l., extending southeast and moving at 37 km/h (23 mph). The information source included Himawari-8 satellite and UHPP. No further ash clouds were forecast in subsequent outlooks. No Aviation Color Code was stated in this advisory.

According to the Smithsonian / USGS Weekly Volcanic Activity Report, wind was no longer resuspending ash previously deposited on the northern flank of Klyuchevskoy as of late September 2025. Only fumarolic emissions were observed, and the Aviation Color Code was lowered to Green on September 25, 2025.

Klyuchevskoy is a large stratovolcano located in Kamchatka, Russia, and is one of the most active volcanoes in the region. Known hazards include ashfall, lava flows, pyroclastic flows, and lahars. The nearby town of Klyuchi, along with other settlements within 50 km (31 miles), may be at risk during significant eruptive episodes.