IG reported that a high level of activity continued at Reventador during 10-17 May, though cloudy weather conditions sometimes prevented visual observations, particularly during 14-15 May.
Gas-and-ash plumes, often observed multiple times a day as reported by the Washington VAAC, rose as high as 1 km above the summit and drifted mainly NW and W.
Incandescence from the crater and incandescent blocks rolling 600 m down the flanks was visible during 10-13 May.
During the morning of 17 May a new lava flow descended the NE flank.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)