INGV-CT reported continuous ash emission and periodic Strombolian activity from multiple vents, possibly along an E-trending fissure E of Etna’s summit craters, during 10-19 May. Observations were limited due to cloud cover. Ash plumes rose to approximate attitudes of 3.5-7.3 km (11,500-24,000 ft) a.s.l. and sulfur dioxide emissions were elevated. Lava flows that issued from the fissure and another fissure to the N traveled about 6 km E into the Valle del Bove during 13-15 May. Ash-and-gas explosions were occasionally accompanied by roaring noises on 14 May. Explosions and roaring noises were audible on 20 May.
Source: Istituto Nazionale di Geofisica e Vulcanologia Sezione di Catania (INGV-CT) – “Report provided courtesy of the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program.”