Anyone know how this is likely to affect the region?
Esp the USVI
I wouldn’t consider USVI part of this region of islands. These are the Windwards. Very south and near grenada. St vincent is part of the grenadines including Mustique winter resort homes of lots of british royalty/celebs. the clouds could cover hundreds of miles but the tradewinds blow from the east westward mostly. Looks like the wind is taking the cloud to barbados which is very far east of St vincent. Last big volcanic eruption was Montserrat in the Leewards. Other than evacuation of the island i don’t think many around it were effected significantly.