Researchers lowered their 2006 forecast for Atlantic hurricanes for the second time in a month Friday, predicting a slightly below-average season with five hurricanes instead of seven.
"Our August forecast was very high. It stunk," admitted Philip Klotzbach, part of the hurricane research team. "We didn't have the major formations we expected. There was a surprising amount of dry air. It choked them off."
The forecast was released as Tropical Storm Ernesto was downgraded to a rain storm along the East Coast and Hurricane John was forcing evacuations in the Pacific as it neared Baja California.
Two of this season's Atlanta hurricanes will be intense, according to William Gray's forecasting team in Fort Collins.
"Despite the lower predictions, residents living along the U.S. coastline should always be prepared for major storms," Gray said.
His team predicted a 59 percent likelihood that a hurricane would hit the U.S. coastline in September, and a 35 percent chance of an intense hurricane. For October, the forecasters said there was a 14 percent chance a hurricane would strike the coast.
The new forecast was the second time the team had downgraded its expectations in the span of a month.
Last spring, Gray's team called for 17 named storms to form in the Atlantic basin during the June through November hurricane season. They lowered that to 15, and then to 13 in their latest forecast.
As of Friday, five named storms had formed, including Ernesto, which briefly became the season's first hurricane last week and was moving through North Carolina and Virginia on Friday as a tropical depression.
The average storm count for the Atlantic basin is 9.6 named storms, 5.9 hurricanes and 2.3 intense hurricanes per year.
Klotzbach identified several factors for the revised forecast, including higher levels of West African dust over the Atlantic, a warmer eastern equatorial Pacific indicating a potential El Nino event this fall, and dryer tropical Atlantic mid-level moisture fields.
The National Hurricane Center has also lowered its Atlantic storms forecast since spring. In May, it predicted 13 to 16 named storms and eight to 10 hurricanes, with as many as six major ones. In early August, the hurricane center revised that to between 12 and 15 named storms and seven to nine hurricanes.
The 2005 Atlantic hurricane season set a record with 28 named storms and 15 hurricanes, including Katrina, which hit one year ago this week and devastated the Louisiana and Mississippi coasts, reports AP.