Based on pilot reports and observations of satellite imagery, the Tokyo VAAC reported that an ash plume from Sakura-jima rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted 100 km E on 19 April. The next day, the JMA reported that a plume rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted SW.
Source: Tokyo Volcanic Ash Advisory Center (VAAC) – “Reports provided courtesy of the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program.”