Tropical Storm Sam expected to rapidly intensify into major hurricane

Tropical Storm Sam, the 18th named storm of the season, is expected to be at hurricane strength by Friday and could be a major hurricane this weekend, according to the National Hurricane Center.

Sam formed Thursday from Tropical Depression Eighteen and was moving west at 15 mph with maximum sustained winds of 70 mph, as of 11 p.m. Thursday, about 1,560 miles east-southeast of the boundary where the Atlantic Ocean meets the far eastern Caribbean Sea. It is forecast to move west-northwest by Friday.

Sam is expected to rapidly intensify and could be at major hurricane strength Saturday, the center said.

If its maximum sustained winds reach 125 mph as forecast, it would be at Category 3 hurricane strength, making it the fourth major hurricane of 2021.

Sam is the second earliest 18th named storm to form in the Atlantic basin, only behind the 2020 season, the hurricane center said.

It’s too early to tell where it might end up, but the next few days could be crucial in forecasting its path. A fast-developing storm raises the likelihood that it will miss Florida.

“The faster that this system strengthens over the next few days, the more likely it is to re-curve east of Florida, and potentially well east of Florida,” according to AccuWeather meteorologist Randy Adkins.

“[However] if this storm takes a little while longer to organize and develop into a hurricane, then that will likely keep it on a track that’s farther to the south and likely increase the likelihood that Florida could see some impacts from this system.”

Adkins said any potential impact from Sam wouldn’t be felt for another 10 days or so, during the first weekend of October.

Also Thursday, an area of low pressure emerged several hundred miles southeast of Bermuda. Forecasters say there’s low odds for its development over the next couple days as it moves north-northwest, and after that the presence of strong upper-level winds should prevent any further development.

There is also a medium chance that the remnants of the former Tropical Storm Odette could redevelop and become a subtropical storm within the next day or two. It is in the northern Atlantic and is no threat to land.

Meanwhile, a tropical wave is expected to roll off Africa’s west coast by end of the weekend. It’s forecast to move west at 10 to 15 mph and, as of Thursday, odds of its development were low, according to the hurricane center.

Adkins expects hurricane season will remain busy for the next few weeks.

“There’s definitely precedent, and unfortunately it seems like last year is a relatively close match for this year in terms of how things have evolved,” he said in reference to the record 30 named storms of the 2020 hurricane season.

“Obviously, last year was a bit busier but we’re well above average already to date with this hurricane season. Given that, I would anticipate we’re going to have activity continue through the remainder of the month and into October.”

The wind shear that kept former tropical storms Peter and Rose from developing into stronger systems is expected to be weak for the next several days, which will support Sam’s development, as will warm water temperatures in the Atlantic.

“Rose and Peter were in a much more hostile environment, especially Peter,” said Dennis Feltgen, a meteorologist and spokesperson for the National Hurricane Center in Miami. “Sam will certainly be growing into a tropical storm, a hurricane and a major hurricane.”

Tropical Depression Rose was a remnant low by early Thursday. Tropical Depression Peter died out Wednesday night.

The remaining storm names for the 2021 season are Teresa, Victor and Wanda, with more than two months to go.

Should we run out of storm names, late-season storms will no longer carry baffling Greek names like Zeta and Theta that were used last year. Experts have opted to use an overflow list of proper names instead. The list includes Adria, Braylen, Caridad, Deshawn, Emery, Foster, Gemma and Heath.

So far in the Atlantic hurricane season, which runs through Nov. 30, there have been 18 named storms, six hurricanes and three major hurricanes.

Sun Sentinel staff writers Victoria Ballard, David Fleshler and Angie DiMichele contributed to this report.