Activity at the Soufrière Hills Volcano is low, although seismic activity has increased slightly.
The seismic network recorded 16 VT earthquakes, four hybrid events, five long-period events and nine rockfalls this week. There is no clear pattern to the activity, although some of the events occurred together in short bursts. The VT earthquakes were located at shallow depths (typically 2km) beneath the dome. This is the highest level of seismic activity since the ash-venting episode in March 2012, but it is still consistent with a pause in lava extrusion.
Sulphur dioxide measurements on five days this week gave an average output of 281 tonnes per day, with a maximum of 351 and a minimum of 168.
Following the passage of Tropical Storm Isaac, the volcanic plume was blown northwards for much of 23 August and the smell of volcanic gases was noticeable in some inhabited areas.
There were no clear views of the dome this week.
Pyroclastic flows can occur at any time without warning on any side of the volcano, including Gages from where they can travel rapidly into Plymouth. Tracks across the Belham valley are frequently destroyed or heavily modified by flash flooding or lahars, and caution should be exercised crossing the valley during and after rainfall.
The Hazard Level is 2. There is no access to Plymouth or Zone V. There is daytime access (8:00 am to 4:00 pm) to Zone C. Maritime zone W remains daytime transit only (boats may sail through the zone but must not stop).