INGEMMET reported that although cloud cover occasionally prevented visual observations of Ubinas, steam and steam-and-ash plumes were seen during 11-16 February and rose to altitudes of 5.7-6.5 km (18,700-21,300 ft) a.s.l. The plumes drifted NE, N, W, and SW.
Source: Instituto Geológical Minero y Metalúrgico (INGEMMET) – “Reports provided courtesy of the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program.”
Volcano World : Supplement 