'Gremlins' expected to keep hurricanes down this year

The Atlantic hurricane season began on June 1. Forecasters on Aug. 7 said this year's season will be milder than had been expected.

The "quiet" hurricane season might turn out to be even quieter, federal researchers said Thursday in a mid-season forecast update

The National Oceanic and Atmospheric Administration update raised the possibility that no major hurricane would develop in the Atlantic basin and that one fewer named storm could form. In a year when two hurricanes already have formed, NOAA's 1-3 prediction of the number of hurricanes overall also raised the tantalizing possibility that the worst threat could be past.

But Gerry Bell, the lead season forecaster, quickly tamped that down.

"It's possible we only see one more hurricane. It's possible we see four more. We're expecting a below normal season, but that doesn't mean the season shuts down," he said. Noting that the season's first storm, Arthur, made landfall, he added, "People who live along the coast should not let their guard down. We know hurricanes strike in below normal seasons. We've already seen one this year."

For the Lowcountry, Bell's caution is particularly keen. The update comes as the hurricane season moves into its peak - the Cape Verde period from mid-August into October, the period when tropical cyclones tend to form off the African coast and turn into powerful hurricanes as they cross the Atlantic. Those storms pose the greatest threat to the Southeast.

Arthur made landfall July 3 near Cape Lookout, N.C., with 100 mph winds. That's fewer than 300 miles north of Charleston. The storm grew to hurricane strength some 100 miles offshore of Charleston.

Arthur and Hurricane Bertha earlier this month gave the season as many storms as formed during the entire 2013 season, noted Jeff Masters of Weather Underground, crediting the Weather Channel. The last time that happened was 1983. On average two hurricanes don't form in the Atlantic Basin until late August.

Bertha, like Arthur, passed offshore Charleston.

The NOAA update calls for 7-12 named storms, down one from its pre-season forecast and 0-2 severe hurricanes with winds more than 110 mph, also down one.

The update follows a July 31 update by the Tropical Meteorology Project at Colorado State University that held to the project's pre-season forecast of below average activity. The project also held to its estimate of a 12 percent chance of a hurricane making landfall in South Carolina and a 3 percent chance of a major hurricane coming in here. Both are below the long-term averages.

The usual hurricane-daunting gremlins are at work: cooler than expected sea surface temperatures and persistent strong high altitude "shear winds" that disrupt tropical cyclones, among other climate conditions.

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