During 18-19 April, the Darwin VAAC reported that low-level ash-and-steam plumes from Rabaul were observed on satellite imagery drifting ESE. According to the VAAC, RVO advised that ash eruptions continued and rocks were expelled during explosions. RVO reported several explosions on 21 April. Billowing ash plumes drifted W and SE during 21-23 April, and caused ashfall about 2 km away in N Matupit on 22 April and areas downwind on 23 April.
Sources: Steve Saunders, Rabaul Volcano Observatory (RVO), Darwin Volcanic Ash Advisory Center (VAAC) – “Reports provided courtesy of the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program.”
Volcano World : Supplement 