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Tropical Depression Twenty could form into the season's 8th hurricane, forecasters say. Hurricane Sam remains powerful

Robin Webb And Angie DiMichele, South Florida Sun Sentinel on

Published in Weather News

Tropical Depression Twenty, which formed Wednesday in the far eastern Atlantic, is expected to quickly strengthen into Tropical Storm Victor then become a hurricane in within days, according to the National Hurricane Center.

If Victor forms, it would be the season’s 20th named storm. If it reaches hurricane strength, it would be the season’s eighth.

Despite the presence of storm-shredding wind shear in the coming days, Tropical Depression Twenty appears hardy. It has the potential “to reach the [far eastern Caribbean] Leeward Islands late this weekend or early next week,” according to AccuWeather senior meteorologist Dan Kottlowski.

As of 11 a.m., Tropical Depression Twenty had top winds of 35 mph, just 4 mph under the minimum threshold for tropical storm formation. It was moving west-northwest at 14 mph.

There’s also an area of low pressure just to the west Tropical Depression Twenty, but it has low odds of developing into a tropical depression. It’s possible the low-pressure area will be absorbed into the stronger system to its east, forecasters said.

If two more storms form this season — Victor and Wanda — experts say 2021 will rank third in the record books for the number of named storms generated in one hurricane season.

Victor and Wanda are the last remaining storm names for 2021. Any subsequent storms would be named using an overflow list, which includes Adria, Braylen, Caridad, Deshawn, Emery, Foster, Gemma and Heath.

Meanwhile, Hurricane Sam’s intensity is forecast to begin a slow decline Saturday as it encounters cooler water temperatures and storm-shredding wind shear, but until then it is forecast to remain a powerful major hurricane, forecasters said.

Sam was at Category 4 strength early Wednesday, with its top winds dipping overnight from 140 to 130 mph, in a busy hurricane season that’s continuing to move up in the record books.

If Sam holds to its major hurricane status for the next three days as forecast, meaning Category 3 or above, “Sam will be only the fourth Atlantic hurricane to form on or after Sept. 23 and be a major hurricane for seven or more days” according to Colorado State University hurricane expert Phil Klotzbach. The other hurricanes being Hurricane Matthew in 2016, Great Charleston in 1893, and Hurricane 7 in 1878.

 

Sam, the fourth major hurricane of 2021, is expected to maintain its movement to the northwest and speed up, then head north Friday then northeast, turning it well away from Florida and the Caribbean, but bringing it closer to Bermuda.

Though Hurricane Sam remains out over open water, it has the potential to create life-threatening surf and rip currents that could reach the U.S. East Coast this week, impacting Florida north to New York.

As of 11 a.m. Wednesday, Sam was about 405 miles east of the islands of the northeastern Caribbean, moving northwest at 9 mph, with its hurricane-force winds extending 40 miles from its center.

Sam was the fifth storm this season — along with Elsa, Grace, Ida and Larry — to undergo rapid intensification, meaning that its top winds increased by 35 mph or more within 24 hours. On Saturday, it swiftly intensified from a Category 2 hurricane to a Category 4. On Sunday, Sam’s maximum sustained winds were less than 10 mph from the minimum threshold for a Category 5 hurricane.

The 2021 hurricane season is currently in a five-way tie for fourth place “in terms of the number of named tropical systems at 19 in one season,” the others being 1887, 1995, 2010, 2011 and 2012, AccuWeather experts said.

With 19 named storms already this season, that’s well above the long-term average of 10.5 named storms by Sept. 28 in previous years, for the period 1999 through 2020, according to Klotzbach. The record-setting 2020 season had 30 named storms in all.

As of Wednesday, conditions were no longer favorable for the remnants of Tropical Storm Peter to redevelop, according to the hurricane center.

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©2021 South Florida Sun Sentinel. Visit at sun-sentinel.com. Distributed by Tribune Content Agency, LLC.
 

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