EL NIÑO GAINS STRENGTH

Dec. 7, 2006 — The latest El Niño/Southern Oscillation Diagnostic Discussion,
produced
by scientists at the NOAA Climate Prediction Center, indicates El Niño
conditions are now
evident in the tropical Pacific and should intensify during the next one to
three months.
However, this episode is expected to be much weaker than the very strong
1997-1998 El
Niño event. (Click NOAA image for larger view of winter outlook for December
2006
through February 2007, including the position of the jetstream and what this
moderate El
Niño event is expected to produce. Click here for high resolution version.
Please credit
"NOAA.")

"Evolving current conditions in the equatorial Pacific are likely to cause a
substantial
increase in sea surface temperature along the west coast of South America in
late
December 2006 and January 2007," said Vernon Kousky, Ph.D., NOAA's lead El Niño
forecaster. "At about the same time, rainfall is expected to increase over the
warm waters
in the central equatorial Pacific, thus setting the stage for typical El Niño
effects over the
U.S. during January through March 2007," he added.

El Niño events influence the predominate position and strength of the jet stream
over the
Pacific Ocean, which in turn affect winter precipitation and temperature
patterns across the
country. During El Niño events, the jet stream is stronger than normal across
the southern
U.S. As a result, increased storminess and wetter-than-average conditions occur
across
the southern tier of the U.S. from central and southern California across the
Southwest to
Texas and across the Gulf Coast to Florida and the Southeast. Meanwhile,
drier-than-
average conditions are experienced in the Ohio and Tennessee Valleys, and in the
northern
Rockies. (Click NOAA satellite image for larger view of sea surface temperature
anomalies
as of Dec. 5, 2006. Click here for high resolution version. Please credit
"NOAA.")

"NOAA's investment in climate models is paying off," said Jim Laver, director of
the NOAA
Climate Prediction Center. Statistical and coupled model forecasts, including
the NOAA
National Centers for Environmental Prediction Climate Forecast System, show El
Niño
conditions peaking during the northern hemisphere winter (December 2006 through
February 2007) and then weakening during the northern hemisphere spring (March
through May 2007). "This event may be with us for a while, and we will be
closely
monitoring how the atmosphere reacts," he said.