Where did the hurricanes go? Dry air, wind shear are muting storm season

aerial view of home destroyed by hurricane

 Image: Wikimedia Commons

Though few people may complain, the hurricane season for 2014 appears to be a near non-event, and several factors have combined to prevent hurricane formation, says a Texas A&M University storm expert.

Robert Korty, associate professor in Texas A&M’s Department of Atmospheric Sciences, says this year’s less-than-active storm season is attributable to unfavorable conditions in much of the tropical Atlantic.

Dry air in the upper atmosphere and wind shear that prevents storm formation appear to be the main reasons for few hurricanes this year.

Hurricane season runs through Nov. 30, but for Texas, the key date is usually Sept. 10. That’s the peak of hurricane season, and after that date the chances of a hurricane hitting Texas grow slim in a hurry.  Extend that date a few days forward, and history is indeed clear: In the last 165 years, only three storms have hit the Texas coast after Sept. 24.

“It’s been a quiet season so far because of all the dry air in the Caribbean and the central Atlantic Ocean,” Korty explains.

“We typically don’t think about ‘drought’ conditions over the oceans, but that’s a fair description of the atmosphere over part of the Atlantic. The air aloft is dry and hot and that inhibits storm formation.”

In an average year, there are about 11 tropical storms in the Atlantic, six of which become hurricanes and three become major hurricanes (rated as Category 3 or higher with winds of 111 miles per hour or higher.)

So far this season, there have been only two named Atlantic hurricanes, Arthur, which formed on July 1, and Bertha on Aug. 1.  Arthur made landfall in North Carolina in July as the first Category 2 hurricane to strike the U.S. coast since Ike hit Texas in 2008.

“History shows that there have been some major storms late in the hurricane season, but generally, they rarely happen,” Korty adds.

“There is still time for some major hurricanes to develop and the next couple of weeks could determine how strong or weak this hurricane will be.

“We’ve been lucky the past few years because the hurricanes that do develop tend to veer away from the Gulf and East coasts.  We’ll have to see if that remains true this season.”

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