Seismicity from Nevado del Huila increased during 9-12 April then again on 13 April, prompting INGEOMINAS to raise the Alert Level to Orange (the second highest level on a 4-color scale). During 13-14 April, seismic signals possibly indicated an eruption. According to news articles, authorities ordered about 15,000 people to evacuate. On 14 April at 2325, the Alert Level was raised to Red, the highest level, based on the seismicity. Seismic events decreased in number and intensity in the early evening of 15 April; the Alert Level was lowered to Orange. Weather inhibited visual observations and overflights of the summit.
Sources: Instituto Colombiano de Geología y Minería (INGEOMINAS), CNN – “Reports provided courtesy of the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program.”