Hurricane Sam continued strengthening late Saturday night, as the Category 4 storm crept closer to Category 5 status with its top sustained winds measured at 145 mph winds a day before forecasters expected. It is the fourth major hurricane of the 2021 season.
The rapid intensification — Sam was a Category 2 hurricane with 110 mph winds early Saturday morning — is expected to continue throughout the night. The maximum sustained winds for Category 4 storms range from 130 mph to 156 mph.
At this point, Sam isn’t expected to threaten South Florida. In fact, the hurricane center shifted Sam’s forecast cone to the north and east since its last advisory, thanks to a trough expected to develop over the western Atlantic over the coming days, which should cause the storm to decrease its forward speed and turn toward the northwest early next week and avoid a direct hit to the eastern Caribbean islands.
As of Saturday’s 11 p.m. advisory, Sam was about 990 miles east-southeast of the eastern Caribbean and moving west-northwest at 8 mph.
The National Hurricane Center describes Sam as a “small storm” with hurricane-force winds extending 30 miles from Sam’s center and tropical-storm-force winds extending 105 miles from its center.
Sam’s growth is expected to level off a bit early next week as it runs into wind shear, but it’s expected to remain a major hurricane for a few days.
Elsewhere, Teresa, the 19th named storm of the season, fully dissipated at the 2 a.m. Sunday advisory.
Teresa was the second-earliest 19th named storm to form in the Atlantic basin, only behind the 2020 season.
Also, 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 it has a medium chance of development in five days. The hurricane center said the system could turn into a tropical depression by the middle of next week.
A broad area of low pressure could form over the eastern or central tropical Atlantic early next week, to the west of the tropical wave that will be moving off the coast of Africa. Environmental conditions appear favorable for some development of this disturbance while it moves slowly westward through the middle of next week.
AccuWeather meteorologist Randy 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.
The remaining storm names for the 2021 season are 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 19 named storms, seven hurricanes and four major hurricanes.