TAMPA, Fla. (WFLA) — So-called “steering currents” will decide the fate of Hurricane Lee’s impact on the U.S. as forecasts show it strengthening to an “extremely dangerous” major hurricane by the end of the week.

On Wednesday, the National Hurricane Center said Hurricane Lee was located about 1,035 miles east of the Northern Leeward Islands. Lee was moving at around 14 mph with maximum sustained winds of 80 mph.

Lee is expected to strengthen into a major hurricane by Friday as warm waters and weak wind shear provide the necessary conditions for additional development.

Though the storm’s exact track is still uncertain, Max Defender 8 Meteorologist Rebecca Barry said, “The important part is it’s making that turn to the north. We know stronger storms tend to make that turn earlier and we’ve also got some steering currents out there that are helping guide that system to the north.”

“We’ve also got the jet stream coming off of the southeast of the US and that’s going to make it a pathway for this system to go,” Barry added.

“The worst environment that it’s going to face over the next four to five days is right now with its weak shear. Conditions are only expected to get better here,” WKRG Chief Meteorologist Ed Bloodsworth said. “We could be talking about a very strong – maybe even a high-end Category 4 hurricane even if it doesn’t make any kind of direct landfall.”

The NHC said swells from Lee are expected to reach portions of the Lesser Antilles on Friday. The swells will likely cause life-threatening surf and rip current conditions.