Residual volcanic ash from Klyuchevskoy volcano observed up to 7 010 m (23 000 feet) a.s.l., Kamchatka Peninsula, Russia

Volcanic ash from Klyuchevskoy in Russia was observed at 7 010 m (23 000 feet) above sea level at 06:00 UTC on October 15, 2025. The advisory was issued by the Anchorage VAAC at 06:00 UTC on October 15, 2025.

The observed ash cloud reached up to flight level 230, which corresponds to approximately 7 010 m (23 000 feet). This information was confirmed using Himawari satellite imagery. The current Aviation Color Code is Orange. The ash was described as residual from a previous eruption, with no new eruption reported in the advisory. The forecast showed the ash cloud at the same altitude for up to six hours after the observation time. No further ash movement or new emission forecasts were provided beyond that period.

According to the Smithsonian/USGS Weekly Volcanic Activity Report for late September 2025, only fumarolic emissions have been observed at Klyuchevskoy and wind-driven resuspension of ash has ceased. The Aviation Color Code was lowered to Green on September 25, 2025, indicating reduced activity and minimal aviation hazard at that time.

Klyuchevskoy is a large stratovolcano located on the Kamchatka Peninsula. Known hazards include ashfall, pyroclastic flows, and lava flows. The nearby settlement of Klyuchi is located approximately 30 km (19 miles) to the northeast. Other small communities may also be affected by ash dispersion depending on wind direction and eruption intensity.