INGV reported that during 15-21 April activity at Stromboli was characterized by ongoing Strombolian activity and degassing from multiple vents within the crater terrace, though activity intensified on 19 April.
Explosions originated at a rate of 3-16 per hour mainly from two vents (N1 and N2) in Area N (north crater area, NCA) and at least four vents (including C, S1, and S2) in Area C-S (South Central crater area).
Explosions from the N1 vent ejected lapilli and bombs mixed with ash no more than 150 m high.
Low-intensity explosions at the N2 vent ejected tephra to heights under 80 m.
Vent C produced gas emissions.
Incandescent material from S1 jetted as high as 150 m above the crater.
Explosions from two vents at S2 ejected tephra more than 150 m high.
Source: Sezione di Catania - Osservatorio Etneo (INGV)
Asosan (Japan)