By Sharon Omahen
University of Georgia
The return of an El Niño climate pattern in the Pacific Ocean will make the Georgia, Florida and Alabama weather colder and wetter this fall and winter, says University of Georgia agrometeorologist Joel Paz. But residents of these states will fight fewer hurricanes.
Paz tracks climate patterns as a member of the Southeast Climate Consortium, offering advice on neutral, El Niño and La Niña climate phases. The SECC also includes UGA state climatologist David Stooksbury and his Florida State counterpart David Zierden.
The SECC's fall climate outlook for Georgia, Florida and Alabama is based on an El Niño that has returned for the first time since 2003, said Paz, a UGA College of Agricultural and Environmental Sciences faculty member.
Started in July, will last through winter
The condition began in July, when unusually warm sea surface temperatures appeared along the equator around the International Date Line, Paz said. It has since spread all the way to the coast of South America.
Over the past two weeks, Paz said, the spread of unusually warm water has taken on the traditional El Niño pattern.
"It's very likely that the current El Niño will intensify further and last through the winter of 2007," he said.
So how will this El Niño affect the Southeastern climate?
"El Niño normally reaches peak intensity and coverage in the winter," Paz said. "The first impact felt in the Southeastern U.S. has been the relatively inactive hurricane season. In spite of predictions to the contrary, 2006 has been a quiet tropical season so far, and many are blaming the developing El Niño."
El Niño is known to create an environment of high shear (winds changing with height) over hurricane formation regions in the Atlantic, Caribbean and Gulf of Mexico, Paz said. This hinders hurricane development.
"With El Niño continuing to grow and the hurricane season more than half over," he said, "we expect below-average activity the remainder of the hurricane season."
The decrease in tropical activity combined with the El Niño will actually bring drier-than-normal weather to Florida, southern Alabama and southern Georgia in September and October, Paz said. The El Niño is not expected to influence the temperatures during these months.
The climate in the Southeast would be fairly dry in the fall without the impact of a tropical system.
More rain, colder temps
But from November to March, SECC experts say the El Niño may bring more frequent storms, excessive rainfall and cooler temperatures to Florida and coastal Alabama and Georgia.
The increased rainfall and cloudiness associated with El Niño will cause average temperatures to be cooler than normal during the winter, Paz said. However, the El Niño should actually reduce the risk of severe cold outbreaks in the Southeast.
"The cooler temperatures should result in greater chill accumulations over the course of the season," he said. "But the strong subtropical jet stream that is typical of El Niño blocks the intrusions of cold Arctic air masses."
To view detailed SECC climate forecasts, see the consortium's Web site at www.agclimate.org.
(Sharon Omahen is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.)