 On September 22 , about 3 days before the system had formed into a tropical storm , its significant rainfall in the eastern Caribbean prompted flash flood warnings in Puerto Rico and the British Virgin Islands . In the Dominican Republic a green alert was issued for provinces in the eastern part of the nation . The next day yellow alerts were issued for eight provinces and red alerts in eight more . Evacuations began in vulnerable San Pedro de Macoris , La Romana , and Barahona and San Jose de Ocoa . The system moved westward on September 23 , threatening Haiti with its rains which prompted the issuance of heavy rain warnings and a red alert warning by the nation 's government . 
