Seismic activity at the Soufriere Hills volcano during the night has remained at about the same slightly reduced level seen during the day time on 19 April. It is still dominated by the occurrence of small, repetitive hybrid earthquakes at a rate of about one per two minutes. Several rockfalls from the dome were recorded some of which generated small ash clouds. A small explosion at 06:56 on 20 April generated a small ash plume which drifted towards the northwest. Intermittent low amplitude broadband tremor was also recorded at the Gages seismic station throughout the whole period.
Moderate viewing conditions early in the morning from the Observatory and Bramble Airport Tower reveal that the new inclined spine is still in position, with the front part possibly broken off and just lying on the dome. Vigorous steam emission from the area around the spine and from several areas of the dome continues, generating a plume which drifts towards the northwest and a pale blue haze in the Upper Gages area.
In spite of the slightly reduced level of activity at the Soufriere Hills volcano during the past 36 hours, scientists at the MVO still view the situation with grave concern. The MVO continues to urge that visits to the evacuated zone be kept to a minimum. The Tar River, Long Ground and Whites areas are extremely dangerous, and should not be entered under any circumstances.