Based on NOTAM‘s (“Notices to Airmen”), the Washington VAAC reported that on 9 December a possible gas-and-ash plume from Fuego rose to an altitude of 4.9 km (16,000 ft) a.s.l., drifted N, and dissipated rapidly. INSIVUMEH reported that on 12 December explosions produced ash plumes that rose to altitudes of 4.1-5 km (13,500-16,400 ft) a.s.l. and drifted SSW. The explosions produced rumbling and degassing sounds, and shock waves were detected 10 km away.
Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH), Washington Volcanic Ash Advisory Center (VAAC) – “Report provided courtesy of the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program.”