Volcanic ash continues to fall and warnings of additional danger are looming.
Pyroclastic flows “contain a high density mixture of hot lava boulders, pumice, ash and volcanic gas. They move at very high speed on volcanic slopes, usually following valleys,” according to the USGS and “destroy almost everything in their path”.
“Based on visual observations and satellite images, the intervals are associated with periods of explosive activity or improved ventilation,” he said.
“Thunder and lightning were felt during these times.”
The ashes continued to fall on the island overnight and also affected neighboring islands, the Grenadines, Barbados and Saint Lucia, he said. “The explosions and accompanying ash fall, of a similar or greater magnitude, will likely continue to occur over the next few days.”
Prime Minister Ralph Gonsalves declared a disaster alert prompted by a change in the eruptive activity of the volcano on Thursday. He has issued an evacuation order for all residents living in what is considered a “red zone”. Gonsalves said it would take four months for life to return to normal on the island.
Authorities said it is likely that explosive eruptions could continue “for days and possibly weeks” after Friday’s first eruption emitted an ash plume that extended to 20,000 feet (6 096 meters) in the sky.
La Soufrière is located on the largest island in the chain of Saint Vincent and the Grenadines.
Patrick Oppmann of CNN reported from Havana and Claudia Dominguez from Atlanta. CNN’s Susannah Cullinane, Theresa Waldrup and Radina Gigova also contributed to this report.