The Meteorological Service says Tropical Storm Ian is now southwest of the island as it moves towards Cayman and Cuba.
In its latest bulletin, the Met Office says as the storm continues to drift westward, its outer bands are still expected to produce moderate to heavy rainfall and thunderstorms across the island, especially southern and northeastern parishes tonight through to Tuesday.
The Meteorological Service says the flash flood warning is in effect for St Mary, Portland, St Thomas, Kingston, St Andrew, St Catherine, and Clarendon.
This means that flooding has been reported or will occur shortly.
The Met Service also says a flash flood watch is in effect for similar areas of Manchester, St Elizabeth, and Westmoreland.
