Rockfall activity continued yesterday evening and throughout the night at a similar level to that which has been noted for the past few days. The highest activity during this period was between 4 and 6:30 this morning. Apart from rockfall signals, no other seismic events were recorded overnight. The presence of rockfall activity with such a low level of other seismicity has been seen before and suggests that the dome is growing quite freely at present.
Visibility is poor this morning, with the crater area covered by clouds. Observations late yesterday afternoon and evening indicated that the dome is still active in a number of places, and small rockfalls were being generated on a semi-continuous basis with occasional larger rockfalls and small pyroclastic flows. The dome appeared to have stabilised somewhat over the previous day or so, with the uppermost part of the dome not as steep or liable to collapse as it had been. Glowing on the dome could be seen yesterday evening and early this morning from the MVO thanks to the cloud-free conditions on the volcano.
The continued high level of rockfall activity suggests that the lava dome within English's Crater is still growing rapidly, and a collapse of part of the dome could occur soon, producing pyroclastic flows and ash. Should the collapse be very large, then an explosive eruption is possible, in the same way that it followed a major dome collapse on September 17/18. All residents of Montserrat are reminded of the potential hazards from the volcano during dome collapses and explosive eruptions, which include pyroclastic flows, falling rocks and ash.