According to CONRED, a 17 December INSIVUMEH report noted changes in Pacaya’s behavior. On 19 December, CONRED issued a bulletin noting that INSIVUMEH reported observations of white and blue “smoke” plumes. The plumes rose to an altitude of 2.8 km (9,200 ft) a.s.l. and drifted S. Lava flows were unchanged from previous days. Based on these reports, CONRED raised the Alert Level to Yellow in surrounding communities.
Source: Coordinadora Nacional para la Reducción de Desastres (CONRED) – “Reports provided courtesy of the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program.”