Semeru, Eastern Java, Indonesia

Based on pilot observations, the Darwin VAAC reported that a plume from Semeru rose vertically to an altitude of 6.1 km (20,000 ft) a.s.l. on 21 April.

Source: Darwin Volcanic Ash Advisory Centre (VAAC)  - “Reports provided courtesy of the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program.”