Seismic activity at La Soufrière Volcano changed with an explosive activity at 6:30 AM today Tuesday, April 13.
Prior to the explosion, long-period (LP) earthquakes had been increasing in number. The explosion was accompanied by high-amplitude seismic tremor which was followed by over three hours of lower-amplitude continuous seismic tremor.
Once this tremor died down, LP earthquakes were recorded, again slowly growing in numbers. However, these LP earthquakes were significantly smaller than those prior to the 6:30 AM explosion.
The vulcanian explosions which occurred at 6:30 this morning, pulsed for ~30 minutes and produced pyroclastic density currents (PDCs) that reached the sea at the mouth of the Wallibou river, ~6 km from the volcano.
Eyewitness accounts of this flow indicate that it had extended further into the sea when it reached the coastline. Observations made this afternoon from the coastline indicate that PDCs resulting from this morning have reached the sea in every valley extending from Larikai to Wallibou.
The volcano continues to erupt explosively and has now begun to generate pyroclastic density currents. Explosions and accompanying ashfall, of similar or larger magnitude, are likely to continue to occur over the next few days.
Alert level remains RED.
Eighty-six shelters with 3,930 occupants are now activated.
Some 446 families are hosting over two thousand persons to date and registration of persons in private sheltering is continuing.
The National Emergency Operations Center continues to be fully functional operating on a twenty-four hour, around the clock basis.
NEMO will continue to provide regular updates on activities at the Volcano as they occur.