KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 7-8 and 11-13 December.
A small explosion, recorded at 1222 on 12 December, generated an ash plume that rose 6.5-6.8 km (21,300-22,300 ft) a.s.l.
That same day a gas-and-steam plume, containing a small amount of ash and drifting 150 km NE, was visible in satellite data.
The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)