Hurricane Lee: How close will it get to the United States

Hurricane Lee is expected to strengthen further on Friday after rapidly transforming into a powerful Category 5 storm with destructive maximum sustained winds of 165 mph as it spins hundreds of miles east of the Caribbean, according to the National Hurricane Center's 5 a.m. ET advisory.
The hurricane was about 630 miles east of the northern Leeward Islands, according to a 5 a.m. update from the National Hurricane Center.
Lee is expected to reach its peak intensity this weekend and remain a dangerous hurricane over the southwestern Atlantic early next week, though it is too early to tell whether this system will directly impact the United States mainland. Dangerous surf and rip currents will hit the northern Caribbean on Friday and the United States on Sunday, according to the center.
Lee is expected to turn north early next week, according to computer model trends. But when that turn happens, and how far west Lee can track by then, will determine how close it gets to the US.
Here's what's guiding the storm, as well as two possible scenarios for how the US threat might play out.
How close will it get to the United States
The Bermuda High, an area of high pressure over the Atlantic, will have a significant impact on how quickly Lee turns. The Bermuda High is expected to remain very strong through the weekend, keeping Lee on its current west-northwestward track and slowing it slightly.
As the high pressure system weakens next week, Lee will be able to begin moving northward.
When Lee makes that turn to the north, the position of the jet stream – strong upper-level winds that can change the direction of a hurricane's path – will influence how close hurricane Lee is to the United States.
Scenario: Out to Sea
If high pressure weakens significantly, Lee could make a quick turn to the north early next week.
If the jet stream forms along the East Coast, it will act as a barrier, keeping Lee from approaching the coast. This scenario would keep Lee away from the US coast while bringing the storm closer to Bermuda.
Scenario: Near the East Coast
Because the high pressure remains strong and the jet stream sets up farther inland over the Eastern US, Lee could make a slower turn to the north. In this scenario, portions of the East Coast, primarily north of the Carolinas, would be vulnerable to a much closer approach from Lee. 
All of these variables have yet to be determined, and the hurricane is still at least seven days away from posing a threat to the East Coast. Lee's potential impact on the United States will become clearer as it moves west in the coming days.