CNN –
Hurricane Lee weakened slightly to a Category 4 storm Friday morning after a day of historic strength intensification into a strong Category 5 storm, a rare occurrence in the Atlantic.
The hurricane packs destructive maximum sustained winds of 155 miles per hour and is spreading approximately 550 miles east of the Northern Leeward Islands.
“Although current leeward intensity is less than the peak overnight, the hurricane remains very strong,” the National Hurricane Center said, noting that further minor fluctuations in maximum winds are expected over the next few days.
Lee is expected to remain a major hurricane over the southwest Atlantic early next week, although it is still too early to tell whether this system will have a direct impact on the U.S. mainland.
Lee, which was a Category 1 storm on Thursday, strengthened at an extraordinary rate in warm ocean waters, doubling its wind speed in just a day.
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The storm’s wind strength increased by 85 miles per hour in 24 hours, marking the third-fastest rapid intensification in the Atlantic along with Hurricane Matthew, according to NOAA research meteorologist John Kaplan. The monstrous hurricane hit Haiti in 2016, killing hundreds in the Caribbean country while also wreaking havoc in parts of the southeastern United States.
Dangerous surf and rip currents will spread across the northern Caribbean on Friday and begin affecting the U.S. mainland on Sunday.
The center of Lee will pass north of the Leeward Islands, Virgin Islands and Puerto Rico this weekend and early next week. Some of these islands could experience tropical storm conditions and life-threatening surf and rip currents over the weekend.
CNN Weather
A satellite view of Lee at Category 5 strength.
Lee hit a rare strength that few storms have ever achieved. According to NOAA’s hurricane database, only 2% of Atlantic storms reach Category 5 strength. Including Lee, only 40 Category 5 hurricanes have passed through the Atlantic since 1924.
Category 5 is the highest level on the hurricane wind speed scale and has no maximum score. Hurricanes reach this level when their sustained winds reach them 157 mph or higher. A 165 mph storm like Lee falls into the same category as Hurricane Allen, the strongest Atlantic hurricane on record, which reached a top speed of 190 mph in 1980.
Hurricanes need the perfect mix of warm water, moist air, and light high-altitude winds to intensify enough to reach Category 5 strength. Lee had it all, especially warm water in the midst of the warmest summer on record.
According to David Zierden, Florida’s state climatologist, sea surface temperatures in the portion of the Atlantic Ocean that Lee passes through are an incredible 2 degrees Celsius (3.6 degrees Fahrenheit) above normal, after rising to “well above record levels” this summer are.
Reaching Category 5 strength has become more common in the last decade. Lee has been a Category 5 since 2016, meaning 20% of these exceptionally strong hurricanes recorded in NOAA’s hurricane database have occurred in the last seven years.
The Atlantic isn’t the only ocean to spawn a massive storm in 2023. In all seven ocean basins where tropical cyclones can form, one storm has reached Category 5 strength so far this year, including Hurricane Jova, which reached Category 5 status in the East Pacific earlier this week.
Computer modeling trends for Lee have shown the hurricane turning northward early next week. But exactly when that turning point occurs and how far West Lee will advance by then will play a big role in how close it gets to the United States.
Several controlling factors at the surface and in the upper layers of the atmosphere will determine how close Lee comes to the East Coast.
Lee’s possible trajectory next week will be determined by several atmospheric factors, including a strong area of high pressure to the east (yellow circle) and the jet stream (silver arrows) to the west.
An area of high pressure over the Atlantic known as Bermuda High will have a big impact on how quickly Lee shifts. The Bermuda high is expected to remain very strong into the weekend, which will keep Lee on his current west-northwest course and slow him down somewhat.
As high pressure subsides next week, Lee may begin to move north.
Once that turn northward occurs, the position of the jet stream — strong high-altitude winds that can change the direction of a hurricane’s path — will influence how close Lee is to the U.S.
Scenario: Out into the sea
Lee could quickly turn north early next week if high pressure weakens significantly.
As the jet stream forms along the East Coast, it acts as a barrier, preventing leeward winds from approaching the coast. This scenario would keep Lee further from the U.S. coast, but could bring the storm closer to Bermuda.
Tracking Scenario: An area of high pressure (yellow circle) east of leeward and the jet stream (silver arrows) west of leeward may cause the storm to track between the two, away from the U.S. coast.
Scenario: Near the east coast
Lee could turn north more slowly as high pressure remains robust and the jet stream continues to form inland over the eastern US. This scenario would leave portions of the East Coast, primarily north of the Carolinas, vulnerable to a much closer approach from Lee.
Chase Scenario: A high pressure area (yellow circle) east of lee and the jet stream (silver arrows) west of lee may cause the storm to travel closer to the US coast between both directions.
All of these factors have yet to come into focus, and the hurricane is at least seven days away from posing a threat to the East Coast. Any potential implications for the US will become clearer in the coming days as the Lee moves west.