(Bloomberg) -- The Atlantic should have a near-averagestorm season, producing four to eight hurricanes before it ends inNovember, according to National Oceanic and Atmospheric AdministrationAdministrator Kathryn Sullivan.

Ten to 16 named storms are likely for the season that officiallystarts June 1, the agency said. A system gets a name when its windsreach 39 miles (63 kilometers) per hour and it becomes a tropicalstorm.

“Near-normal may sound encouraging, relax, everything is OK,”Sullivan said at a press briefing Friday. “The amount of activitythat I just read off actually suggests that we may be in for moreactivity than we have been in recent years.”

Hurricanes can cause a great toll in human lives, aswell as billions of dollars in property damage, while roilingenergy and agricultural markets. On average, 12 storms form in theAtlantic from June 1 through November 30. There were 11 namedstorms last year and eight in 2014.

Gulf energy

About 5% of the U.S. marketed natural gas production comes from theGulf of Mexico, along with 17% of crude oil, according to theEnergy Information Administration. The Gulf region also is home tomore than 45% of petroleum refining capacity and 51 percent of gasprocessing.

Florida, a frequent target of storms, is the world’ssecond-largest orange-juice producer, behind Brazil, according tothe Agriculture Department. More than 6.6 million homes with anestimated reconstruction cost of $1.5 trillion lie in vulnerableareas along the Atlantic and Gulf coasts, said the Insurance Information Institute in NewYork.

The U.S. was last hit by a hurricane in 2014, when Arthur struckNorth Carolina, and was last battered by a major hurricane, withwinds of 111 mph or more, in 2005, when Wilma crossed Florida. Forthe past three years, the total number of storms to form in theAtlantic fell within NOAA’s pre-season forecast.

The coastline from North Carolina to Georgia may be threatenedby a storm this weekend. A low pressure system northof the Bahamas has a 90% chance of becoming either a subtropical ortropical storm this weekend. Reconnaissance aircraft will fly intothe system later Friday.

Off-season storms

“Storms in May are not unusual; we had two in 2012,” Sullivan said.This year’s storm estimates include Hurricane Alex, which formed inJanuary.

People shouldn’t focus on the overall numbers because it onlytakes one storm to cause significant damage, said Laura Furgione,deputy director of the National WeatherService.

Also, a hurricane’s eye and wind speed aren’t good predictors ofwhere the damage or life-threatening effects will occur, shesaid.

“Nine out of 10 fatalities associated with hurricanes arewater-related,” Furgione said.

Sullivan said this year there are unknowns that could affect theeventual outcome of the season. One is whether the waning El Ninoin the Pacific will continue to influence wind shear in theAtlantic early in the season.

Wind shear

El Ninos cause more wind shear, which can rip apart a buddingstorm, in the Atlantic. Sullivan said there is a chance that a LaNina, which reduces shear, could develop at the heart of theseason, from August to September.

Researchers also don’t know if a larger change is coming to theAtlantic, Sullivan said. The ocean alternates between cool and warmphases that last 25 to 40 years. This is called the Atlantic Multidecadal Oscillation.

“The last time we have had a cold phase was 1971 to 1994 and weonly had two above-normal seasons,” said Gerry Bell, a hurricaneclimate specialist at the U.S. ClimatePrediction Center in College Park, Maryland. “That is howstrong that AMO signal really is.”

The past few years have been cooler; however, it is hard to knowif a larger shift is under way, Sullivan said. This will be thefirst time researchers will have watched a transition from warm tocold with modern sophisticated instruments, she said.

“This is the first time we have seen the signals that mightportend a phase shift,” Sullivan said.

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