December 2015 – GUATEMALA – The activity at Fuego might be picking up towards a new paroxysm (eruptive phase with strongly increased effusion rate, resulting in lava fountaining and lava flows). We camped on the SW side of the volcano last night, and observed mild to strong strombolian explosions that occurred at intervals between 1 and 10 minutes. The strongest explosions sent incandescent material to heights of up to approx. 500 m and similar distances. One particularly intense explosion was accompanied by a very strong shock wave.
Although not seen directly from our location, a pyroclastic flow occurred around 10:15 (local time): we observed the co-ignimbrite ash plume rising from what was likely a collapse of a new lava flow on the southern slope. According to staff at the Panimache volcano observatory, who confirmed our observation, the pyroclastic flow could have reached a length of 7 km and seems to herald the start of the 14th paroxysm of Fuego in 2015… Following the initial sighting of the brownish ash plume, it gradually spread around the whole southern slopes and caused fine ash fall in the area lasting about 2 hours, graying all vegetation. –Volcano Discovery