Seismic activity during the night has been slightly lower than during the day time. The seismicity continues to be dominated by the occurrence of small, repetitive, hybrid earthquakes at shallow depths beneath the volcano . Between about 16:00 on 15 April and 01:00 on 16 April, the rate of occurrence of these events was 2 per minute but after that, it decreased to 1 per minute. At the Gages seismic station, the events between 16:00 and 22:00 on 15 April were embedded in a low amplitude broadband tremor. The interpretation that these hybrid events indicate that the rate of dome growth during their period of occurrence is greater has been confirmed by both visual and other instrumental observations.
A few signals interpreted as representing rockfalls were also recorded on the nearest stations of the seismic network but no explosion large enough to have been detected seismically seems to have occurred.
No early morning viewing of the crater area has taken place because of low cloud cover on the mountain.
Scientists at the MVO still remain gravely concerned about the current level of activity at the Soufriere Hills volcano and urge that visits to the evacuated zone be restricted to those that are absolutely essential. The Tar River, Long Ground and Whites areas are now extremely dangerous, and should not be entered under any circumstances.