Just got this info from VITEMA:
An intense low pressure system across the northwest Atlantic is generating large swells that is impacting exposed coastlines of the northern U.S. Virgin Islands. The National weather Service in San Juan has issued a coastal flooding advisory which is in effect through 4 a.m. Saturday and a high surf advisory remains in effect until 8 p.m. Saturday.
These larges long period northwesterly swells could produce large breaking waves of 13 to 16 feet along the northern coastlines of St. Thomas and St. John and up to 4 to 6 feet on St. Croix. The swells are producing strong rip currents making swimming dangerous as well as hazardous surf conditions.
Localized flooding and minor beach erosion are also possible along the northwest through north facing coastlines of the Virgin Islands.
Beach-goers are advised to use extreme caution during recreational activities at local beaches.