By Sharon Omahen
University of Georgia
Most Georgians probably don't care much about weather patterns in the Pacific Ocean. But an unusually cold ocean surface there should bring warmer, drier weather here this spring.
Periodic warming or cooling of tropical Pacific Ocean surfaces, known as El Niño or La Niña, can affect U.S. weather patterns. El Niño brings more winter rains. La Niña has the opposite effect.
"The temperatures in the Pacific Ocean affect the mainland U.S. because they affect the jet stream patterns," said Joel Paz, an Extension agrometeorologist with the University of Georgia College of Agricultural and Environmental Sciences.
Paz said these ocean temperatures were normal for nearly two years. But then "the far eastern Pacific, near the coast of South America, began to cool in October," Paz said.
"The cooling water has since spread westward to the international date line," he said. "The unusually cold sea-surface temperatures are now taking the classic La Niña configuration."
So what does all this mean to you? Georgia, Florida and Alabama will see drier and warmer-than-normal weather for late winter and spring, he said.
Paz says this La Niña event is unusual in that it came late in the season.
"The classic La Niña climate pattern in the Southeastern U.S. corresponds to fall, winter and spring seasons that are generally warmer and 20 percent to 40 percent drier than normal," he said.
More wildfires possible
"La Niña has a bigger impact in south Georgia, below the fall line," he said. "It's also known to bring an active wildfire season to Florida and the coastal plains of Alabama and Georgia."
Paz tracks these weather patterns as part of a multi-university team of researchers who offer advice for neutral, El Niño and La Niña weather phases. Known as the Southeast Climate Consortium, the group shares their weather knowledge via the Internet at www.agclimate.org.
Designed as a resource for farmers, the consortium Web site issues quarterly forecasts for Alabama, Florida and Georgia. It uses data collected from university resources and the National Climate Data Center.
The site is based on more than 50 years of weather data. It provides monthly rainfall and temperature forecasts for Alabama, Florida and Georgia counties.
The consortium's member universities, besides UGA, are Auburn, Alabama-Huntsville, Florida, Florida State and Miami.
The project is funded by the National Oceanic and Atmospheric Administration's Office of Global Programs, the U.S. Department of Agriculture's Cooperative State Research, Education and Extension Service and the USDA's Risk Management Agency.
(Sharon Omahen is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.)