La Soufrière, which has been dormant for decades, first started showing volcanic activity in December which picked up this week.
On Thursday, Prime Minister Ralph Gonsalves urged more than 16,000 residents in "red zones" to evacuate.
The volcano has since spewed dark ash plumes 6 km (3.7 miles) into the air.
Ash fall has been recorded as far from the volcano as Argyle International Airport, St Vincent's National Emergency Management Organisation (NEMO) said.
