Tropical Storm Melissa formed on Tuesday, the 13th named storm of the Atlantic season. It is expected to bring heavy rain to Haiti, the Dominican Republic and Jamaica by the end of the week, but forecasters with the National Hurricane Center said its path and intensity beyond the next few days are “quite uncertain.”

Invest 98L in the eastern Caribbean is expected to strengthen into a tropical depression or tropical storm early this week.

The long-term forecast models have it shifting from its westward path and turning back north, becoming a potential threat from Jamaica to Puerto Rico.