San Juan Radar is indicating at least one, if not two, areas of circulation in the rain and thunderstorms.
One is indicated South of the Mona Passage (SW Puerto Rico) and the other, just off the NW shore of Puerto Rico.

The southern circulation appeared to have more convective type precipitation. And the area on the northern side of Puerto Rico appeared to be more stratiform type precipitation.

Aquadilla and Ponce are reporting lightning this hour.
San Juan, Charlotte Amalie-St. Thomas, and Christiansted are reporting light rain.
Charlotte Amalie and Christiansted were noted to have backing winds over the last few hours.