INSIVUMEH reported explosions from Santa María’s Santiaguito lava dome complex during 15-21 April. Resultant ash plumes rose to altitudes of 4.1-4.7 km (13,500-15,400 ft) a.s.l. and drifted SW. Constant avalanches on the W and S flanks were noted. Based on observations of satellite imagery, the Washington VAAC reported that an ash plume drifted SW on 18 April.
Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH), Washington Volcanic Ash Advisory Center (VAAC) “Reports provided courtesy of the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program.”