The National Hurricane Center's advisory stated Hurricane Chris was located about 200 miles southeast of Cape Hatteras, North Carolina and was moving in a northeastern direction at 10 mph.
The storm, however, may produce unsafe surf conditions, including a high rip along the coast of North Carolina and the mid-Atlantic states in the next few days and potentially creating life-threatening conditions, the NHC said in an advisory.
Met Office spokeswoman Nicola Maxey said that tropical storm Chris, which is building on the USA east coast and is predicted to become a hurricane, "will influence the weather but we can not tell what that influence will be at the moment because it is still developing".
Friday and Saturday our July thunderstorms return mainly late in the afternoon with highs in the lower 90s.
Given the storm's predicted track, the strongest winds were expected to be over Newfoundland's Avalon Peninsula.
Hurricane Chris is expected to pass south of Nova Scotia on Thursday, creating high waves along the Atlantic coast. The hurricane has reached winds of 85 miles per hour, making it a Category 1 storm and the second named hurricane for the Atlantic season.
It also issued a flash-flood watch for the U.S. Virgin Islands through Monday evening.
Storm Chris is set to hit the United Kingdom with gales, cooler temperatures and damper weather, threatening to end Britain's heatwave.
About 7,000 houses and businesses in Puerto Rico still lack power after Maria leveled an electricity grid that was ill-maintained before the storm.