Montserrat Volcano Observatory

Monring Report
Report for the period 16:00 29 July
to 07:00 30 July 1996

Yesterday's activity at the Soufriere Hills Volcano peaked between 4 and 6 pm. During this period there were numerous pyroclastic flows in the Tar River Valley that entered the sea. These flows destroyed almost all the trees in the Tar River Valley.

Large ash clouds were generated by these flows and there was significant ashfall downwind, on the western side of the volcano. Some of this ash was very wet and fell as mud in St Patricks. Lightning discharges, and associated thunderclaps, were seen in the ash clouds. This is a fairly common phenomenon in volcanic ash clouds.

Overnight activity was lower than that at the peak level yesterday, but was at a similar level to that recorded during most of yesterday. There were numerous small rockfalls and probably some small pyroclastic flows in the Tar River Valley area.

The activity yesterday was caused by collapses on the surface of the growing lava dome. There is therefore no increase in hazards to areas outside the evacuated zone. Hazards in some areas of the evacuated zone have increased significantly. The Tar River Valley and surrounding areas are now extremely hazardous, and should not be entered under any circumstances. If activity continues, there is a risk that flows or ash surges may come over the Farrells' Wall. People are advised not to work areas beneath Farrell's Wall.

Montserrat Volcano Observatory