Maria strikes island as a powerful Category 4 storm, inflicting potentially catastrophic damage.
Tropical Storm Isaac passed through the Lesser Antilles, between Dominica and Martinique, with flooding rains and damaging winds approaching 80 kilometres an hour.
The system moved through quickly on Thursday and is now in the eastern Caribbean.
Isaac is currently located about 300 kilometres to the south of St Croix with winds at around 65km/h.
The storm is expected to weaken further over the next few days as it tracks well south of Puerto Rico and Hispaniola.
Isaac is expected to pass by close to Jamaica by the end of the weekend. By that time, it will have become no more than a tropical depression.
Heavy rain and gusty winds are likely across the island and the residents have been advised to keep an eye on the forecast as some flooding is possible, along with damage to trees and power lines.