DC, October 12, 2004 (ENS): This winter will
bring above-average temperatures in Alaska, much of
the West and the northern and central Great Plains,
according to weather forecasters at the National Oceanic
and Atmospheric Administration (NOAA).
The NOAA 2004-2005 Winter Outlook indicates some improvement
in drought conditions in the West, but long-term drought
is expected to persist through the winter in many areas.
Drier-than-average conditions are expected in the Midwest,
northern Plains, and Pacific Northwest.
Elsewhere across the United States, the NOAA Winter
Outlook calls for below average temperatures across
the Gulf Coast states, the Southeast and the mid-Atlantic
In the Northeast, Midwest and parts of the Southwest,
NOAA forecasts equal chances of warmer, cooler or near-normal
temperatures this winter.
California and the southernmost states from coast to
coast can expect wetter than average conditions, forecasters
For the first time, NOAA’s new Climate Forecast
System is being used as a tool for this outlook. This
new system is a coupled ocean-atmosphere computer model,
which complements other NOAA models and gives increased
confidence of probable climate events before they happen.
Dr. Louis Uccellini, director of NOAA’s National
Centers for Environmental Prediction, calls it "a
new era in climate prediction."
“NOAA’s progress in climate forecasting
is based on ongoing research and collaboration with
our partners, advancements in our understanding of the
global climate system, upgrades to the weather and climate
supercomputer, and improvements in the state-of-the-art
atmospheric and oceanic modeling applications,"
The winter outlook reflects a blend of impacts associated
with weak-to-moderate El Niño events in the central
equatorial Pacific Ocean and is based on the likelihood
that these conditions will persist through early 2005,
El Niño influences the winter weather patterns
by affecting the jet stream and the path that storms
take across the eastern Pacific and North America.
“Our winter forecast factors in the effects of
a weak El Niño that may strengthen into a moderate
event during the winter months,” said NOAA Administrator
Conrad Lautenbacher. “But we’ll keep our
eye on other climate features in the Pacific and the
North Atlantic that play an important role on the week-to-week
variability in our winter weather. These patterns influence
the position of the jet stream and dictate where and
how winter storms will move.”
During weak to moderate El Niño events, shifts
in the jet stream change the patterns of storminess
over the eastern North Pacific and North America.
Jim Laver, director, NOAA’s Climate Prediction
Center says, “NOAA anticipates enhanced storminess
near the Aleutian Islands and in the Southeast U.S.,
and warmer, drier conditions over western North America.”
Another climate system called the North Atlantic Oscillation
also plays an important role in modulating the winter
weather over the eastern half of the United States.
This climate pattern influences the position of the
jet stream over the North Atlantic, affecting winter
weather over the Northeast, but it is only predictable
one to two weeks in advance.
Impacts from the North Atlantic Oscillation are included
in NOAA’s Climate Prediction Center's 8-14 day
and 6-10 day outlooks and U.S. Hazards Assessment.