By David Emory Stooksbury
University of Georgia
Athens, Ga. — Drought conditions are expected to continue
across much of Georgia through spring 2008 and may expand into
southeast Georgia by spring. A La Niña climate pattern has
developed, which increases the probability of a dry, warm winter
and spring across most of the state.
Current predictions from the National Oceanic and Atmospheric
Administration Climate Prediction Center are for a weak to
moderate La Niña to persist through early 2008. The climate
pattern may intensify during the next three months, according to
the CPC.
The effects of the La Niña pattern differ with its strength.
These differences are critical across north and central Georgia,
potentially having major impacts on the current drought and the
region’s ability to recover this winter and spring.
A weak La Niña climate pattern typically brings a warm, dry
winter and spring to south Georgia. However, under weak
conditions, there is a transition zone across the piedmont
region, with a tendency toward wetter-than-normal conditions
across extreme north Georgia.
With a moderate to strong La Niña, the transition zone from dry
winters and springs to wetter-than-normal conditions moves to the
extreme northwest corner of Georgia. These conditions would make
the entire state much more likely to have a dry, warm winter and
spring.
Compared to a weak La Niña pattern, the average total rainfall
across north Georgia for November through February is drier with
a moderate pattern by 4.97 inches in Athens, 5.47 in Atlanta,
5.59 in Cornelia, 7.75 in Gainesville and 7.23 in Rome. For
spring (March through May), the moderate pattern is drier by 3.84
inches in Athens, 3.74 in Atlanta, 2.77 in Cornelia, 3.33 in
Gainesville and 0.88 in Rome.
Regardless of the strength of the current La Niña, there is a
significant probability that central and south Georgia will have
a warm, dry winter and spring. If the pattern becomes moderate to
strong, a warm, dry winter and spring will be even more probable.
Across north Georgia, the strength of the La Niña will be
critical in determining where the transition zone between drier-
and wetter-than-normal winter and spring occurs. If the pattern
is weak, the transition region will normally occur south of the
mountains across the piedmont. If it’s moderate, there is a high
probability that all except the extreme northwest corner will be
warm and dry through spring.
The CPC winter outlook is for below-normal precipitation
statewide, with the probability ranging from greater than 65
percent in extreme southeast Georgia to 50-to-55 percent across
the foothills into the mountains. Across middle Georgia, the
probability of a drier-than-normal winter is about 60 percent.
The probability of a warmer-than-normal winter is greater than 60
percent south of a line from near Columbus to near Lincolnton.
North of this line, the probability of a warmer-than-normal
winter ranges from 55 percent to 60 percent.
The CPC spring outlook is drier than normal, with the probability
greater than 60 percent across the southern coastal plain,
between 55 percent and 60 percent across the northern coastal
plain into the piedmont and 50 percent to 55 percent across the
foothills and mountains.
If a moderate La Niña pattern develops, there is a high
likelihood that north and west Georgia won’t be able to recover
from the drought this winter.
The extreme- to exceptional-drought regions of the state may
muddle through the winter and early spring. But without
significant recharge of the soil moisture, groundwater, streams
and reservoirs, conditions next summer could become catastrophic.
Regardless of the strength of the La Niña pattern, areas of
southeast Georgia that aren’t classified as being in drought
could be experiencing drought conditions by spring.
Water-conservation and drought-management tips for home, garden,
landscapes and pets can be found at
www.caes.uga.edu/topics/disasters/drought/home/index.
Get updated drought information at www.georgiadrought.org. The
Web site includes information on how to deal with the drought.
Updated weather information is at www.georgiaweather.net. This
University of Georgia network has 71 automated weather stations
statewide.
(David Emory Stooksbury is the state climatologist and a
professor of engineering and atmospheric sciences in the
University of Georgia College of Agricultural and Environmental
Sciences.)
