The Canadian Hurricane Centre in Halifax says the effects of newly formed Hurricane Bertha could brush parts of Atlantic Canada by late Wednesday.
The storm, which was tracking northward, was located east of Florida on Monday with sustained winds of 130 km/h.
Forecasters say the storm was expected to move south of Nova Scotia with its northern tip expected to spread cloud over the province.
The hurricane centre says rain from the post-tropical phase of the storm may affect the southeastern portion of Newfoundland.
Winds are expected to remain offshore, although there is a small chance they could affect southeastern Newfoundland on either Wednesday or Thursday.
Likely to avoid U.S. East Coast
Ocean swells are also expected along the Atlantic coast of Nova Scotia and in Newfoundland with Bertha likely bringing gales to the Southern Maritimes Marine District and the Grand Banks off Newfoundland.
Forecasters say there is still a large degree of uncertainty with the storm because it could merge with a trough of low pressure.
The newly formed Bertha was continuing to swirl northward across open sea Monday after brushing the Turks & Caicos Islands and Bahamas as a tropical storm. Forecasters predicted the storm wasn't likely to make landfall on the U.S. East Coast, however.
The U.S. National Hurricane Center in Miami said the second hurricane of the Atlantic season also was likely to miss Bermuda while beginning to curve north-northeastward.
The current forecast map predicts that the centre of the storm will stay offshore as it passes wide of the U.S. East Coast, though it's hard to precisely gauge a storm's path days in advance.
The storm buffeted parts of the Bahamas and the Turks & Caicos with rain and gusty winds Sunday, after passing over the Dominican Republic and causing temporary evacuation of dozens of families as its downpours raised rivers out of their banks. Earlier, it dumped rain on Puerto Rico, which has been parched by unusually dry weather.
The storm strengthened to a hurricane Monday morning with maximum sustained winds of near 130 km/h with little change expected in the next 24 hours. It was forecast to start weakening Tuesday. The hurricane was centred about 370 kilometres northeast of Great Abaco Island and is moving north near 28 km/h.