The level of seismic activity during the night has been the same as during the day time. The seismicity is dominated by the occurrence of small, hybrid events at a rate of about 2 to 3 per minute. These small events are detected mainly at the nearest seismic stations and preliminary calculations of locations place them at shallow depth beneath the volcano. Similar events have been recorded several times during the current volcanic crisis at the Soufriere Hills Volcano. These events are interpreted as possibly indicating a further increase in the rate of dome growth.
A few signals interpreted as representing rockfalls were also recorded. Several small explosions were recorded at 19:41, 21:04, 21:22 and 23:19 on 11 April 1996 and 04:34, 06:20 and 06:21 on 12 April 1996. Some of these events were associated with small ash clouds.
Visibility during the early morning from both the Observatory and Bramble Airport was poor.
The scientists at the MVO remain gravely concerned about the current level of activity at the Soufriere Hills volcano and therefore urge people still living in the evacuated zone to leave immediately. Visits to the evacuated zone should 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.