On other days the volcano was obscured by clouds. No seismicity was registered under the volcano. On April 20-21, weak fumarolic activity was observed. On other days, the volcano was obscured by clouds. Seismic activity under Sheveluch volcano increased sharply on April 22.
Clouds obscure the volcano and prevent visual observation.
Seismic activity continued to increase during the week. The number and the energy of the largest events have gradually increased. The course of the present seismic activity suggests that if an eruption occurs, it may be similar to that of April 1993. The 1993 eruption was preceded by a significant increase in volcanic and seismic activity. Mud flows extended from the volcano 15-20 km.