Update, 11 p.m.: Irma remains a Category 3 hurricane with top sustained winds of 115 mph, according to the National Hurricane Center.
In its 11 p.m. advisory, forecasters said the storm was moving west at 14 mph and hurricane-force winds extended out about 25 miles from the center. The official forecast path was nudged northward slightly, but the overall reasoning hadn’t changed.
Update 5 p.m.: Irma has restrengthened to a powerful Category 3 hurricane with 120 mph winds.
The National Hurricane Center said the storm is heading west at 13 mph and is asking people in the Leeward Islands to begin monitoring the system.
Irma is forecast to be a Category 4 hurricane with 130-mph winds as it approaches the Leeward Islands on Tuesday.
Irma’s wind speeds could fluctuate over the next several days as it moves into an area of warmer water, but with higher wind shear that will work against it strengthening.
The official forecast shows no increase in intensity, but forecasters noted this could be “conservative.”
Dan Kottlowski, a hurricane expert with the Pennsylvania-based AccuWeather, said it’s too early to know if the U.S. coastline will be affected by Irma. A clearer picture should emerge Monday or Tuesday.
“It may be a fish storm, but there is no way to tell right now,” Kottlowski said, referring to the nickname given tropical cyclones that head out to sea with no impact to land. “People don’t need to panic and I don’t think it’s worth them worrying about it over Labor Day weekend.”
Still, Palm Beach County emergency managers urged that regardless of Irma’s ultimate destination, the long weekend is a good time to review hurricane plans and take inventory of supplies.
It’s recommended that people have a three-day supply of food and water. After watching rescues continue in Texas on Friday – nearly a week after Hurricane Harvey’s landfall – an additional few days of supplies can’t hurt, said Mary Blakeney, senior manager with the county’s Division of Emergency Management.
“We advertise three to five days for general preparedness, but it’s not a bad thing to have a seven-day supply,” Blakeney said. “We really need people over this holiday weekend to take some time to pay attention to the local media and just be vigilant so there’s no surprise.”
The hurricane center is also tracking a tropical wave over the eastern Atlantic that has a 60 percent chance of development over the next five days.
The wave is moving west at 15 mph and heading into warmer waters with lower winds shear. Forecasters said it could become a tropical depression early next week.
Update 11 a.m.: Hurricane Irma weakened somewhat this morning as it underwent an eyewall replacement cycle, but the compact storm is expected to restrengthen as it moves west-northwest at 13 mph.
The National Hurricane Center set the wind speed at 110 mph at its 11 a.m. advisory, which is a Category 2 storm. Irma is about 1,580 miles east of the Leeward Islands.
Irma is forecast to make a slight turn to the north-northwest on Tuesday, putting it at the doorstep of the Leeward Islands, but it’s path after that is still uncertain.
While the Bermuda High is still a major component in steering Irma, an upper-level low is forecast to drop south on the east side of that high and should be a key feature in how far south Irma goes before making a right turn, forecasters said.
The NHC now has Irma maxing out at the end of five days as a Category 3 storm with 125 mph winds, but it’s still possible it could intensify over the very warm waters of the Tropical Atlantic. The reduction in winds speeds was made because of an uptick in damaging wind shear in front of Irma.
“There is the potential for Irma to ramp up to an even more powerful hurricane this weekend,” according to AccuWeather Hurricane Expert Dan Kottlowski.
Eyewall replacement cycles happen when outer rain bands strengthen, move inward and draw moisture from the inner eyewall. The cycle can temporarily weaken the cyclones.
Forecasters noted that this could happen several times with Irma and that the process is nearly impossible to predict.
Irma will take about a week to make its trek westward across the Atlantic Ocean. Meteorologists will likely be tracking this storm through the middle of September, according to AccuWeather.
“All interests in the eastern Caribbean will need to monitor the progress of this evolving and dangerous hurricane,” Kottlowski said.
Previous story: Major Hurricane Irma, which maintained Category 3 strength this morning with 115 mph winds, continued its trek west-southwest, but its long-term destination remains unclear.
The National Hurricane Center, which is also watching a new disturbance off the coast of Africa, said Irma is traveling south of the Bermuda High which should cause it to turn on a more west-northwest track on Tuesday, putting it closer to the Leeward Islands and Puerto Rico.
But, forecasters stressed the models differ on where Irma will go and that it’s too early to say what, if any, impact it will have on the U.S. coast.
As of the 5 a.m. advisory, Irma was about 840 miles west-northwest of the Cabo Verde Islands with a minimum central pressure of 967 mb.
Just 24 hours ago, Irma was a tropical storm. Forecasters called its rapid intensification from a storm to a Cat 2 and then Cat 3 hurricane in less than a day “impressive.”
Still, Irma is a compact storm at this point, with hurricane-force winds extending out just 15 miles.
As of the 8 a.m. advisory, the hurricane center was giving a tropical wave over the far eastern Atlantic Ocean a 50 percent chance of tropical development. Forecasters said the system could become a tropical depression next week as it moves west at 15 mph over warm waters with low wind shear.
Weather Underground co-founder Jeff Masters notes that Irma’s arrival is about three weeks ahead of schedule for the normal fourth-named hurricane of the season.
“Irma appears destined to become a dangerous long-track major hurricane that could potentially impact the islands of the Caribbean as well as the mainland U.S. next week and the following week,” Masters wrote in his Category 6 blog.
With sea-surface temperatures at more than 1 degree above normal in the tropical Atlantic and light wind shear, the hurricane center has Irma reaching Cat 4 strength with 140 mph winds. Some forecasters even put it at a Cat 5.
“Irma is more than a week away from any possible U.S. impacts,” Masters said. “Bear in mind that, on average, long-range hurricane forecasts beyond 7 days have very little skill when it comes to specific locations and intensities, and much could change in the coming days.”