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NOAA RECAPS SUMMER OF 2000, SAYS LA NIÑA INFLUENCE GONE;
AUTUMN EXPECTED TO BRING CONTINUED WARMTH FOR PORTIONS OF THE
September 20, 2000 In the meteorological record books,
summer 2000 will be remembered for the devastating wildfires
that scorched more than 6.8 million acres across the nation,
the searing temperatures and drought that plagued parts of the
West and South, the historic string of rain-free
days in Texas, which rivaled the Dust Bowl of the 1930s, and
the cooler-than-usual temperatures in the East. For example,
the Washington, D.C., area had its coolest summer since 1972,
and the San Francisco Bay Area, by contrast, had hotter-than-usual
temperatures, including a heat wave with record temperatures
of up to 110 degrees.
(Click image for larger view. Note: This is a very large file
(approx. 7 mb).)
[Photo: D. James Baker, NOAA administrator, discusses summer
and fall weather of 2000 at a news conference in Washington,
But today, NOAA scientists
Niña, the system mostly responsible for the weather
extremes, is not a factor now and do not expect itor its
climatic opposite El Niñoto
influence global weather for the next nine months.
Click images for
here to view animation of Hurricanes Alberto and Gordon and
the tropical depression that eventually became Tropical Storm
The U.S. autumn forecast calls for the enhanced likelihood of
warmer-than-normal temperatures in the Southwest, especially
in the desert Southwest and in the Florida Peninsula. The likelihood
of continued drier-than-normal conditions will prevail in the
Southwest. The Northwest and the Central and Southern Plains
will likely experience wetter-than-normal conditions, but not
enough to eliminate the drought.
"For the first time in three years, global weather will
not be impacted directly by either a strong El Niño or
La Niña," said U.S. Secretary of Commerce Norman
Y. Mineta. "This means a return to more normal weather,
but it also means that long-term seasonal outlooks will be more
uncertain without the firm influence of these climate cycles."
"Now that La Niña
is history,we are at a turning point for our climate pattern,"
said NOAA administrator D.
James Baker. "This climate shift is one that we are
continuing to study, but we know that without the influence of
La Niña and El Niño, seasonal climate forecasting
is more challenging."
El Niño occurs when
sea-surface temperatures in the Equatorial Pacific are warmer
than usual, and La Niña, when the water temperatures are
cooler than normal. Both events influence the atmosphere and
have ripple effects on weather around the world.
NOAA scientists also said a
lesser-known, short-term climate phenomena called the Madden-Julian
Oscillation, is one of several atmospheric features that
can impact the numbers and intensity of tropical storms. The
MJO circulates from west to east around the globe, sometimes
enhancing wind patterns favorable for rainfall. As the pattern
approaches the Americas, other factors being equal, hurricanes
are more likely to occur in the Gulf and Caribbean.
"This climate shift is
one that we are continuing to study," Baker said, adding
that the position of the oscillation could have the opposite
effect and "turn off hurricanes almost completely."
Retired Air Force Brig. Gen. Jack
Kelly, director of NOAA's National Weather Service, said
La Niña's exit will mean a return to more normal.
(Click image for larger view. Note: This is a large file,
approx. 7 mb.) [Photo: Retired Air Force Brig. Gen. Jack Kelly,
director of NOAA's National Weather Service, recaps the summer
of 2000 weather at a news conference in Washington, DC.]
"Summer 2000 was one of
transition, as La Niña faded but went out with a flourish,"
Kelly said, pointing to the recording-setting weather events.
"Conditions to suppress wildfire activity will become more
favorable, especially as we edge closer to the cold months."
season at its peak, and with parts of the East receiving
more rain than normal, Kelly warned of the severe flood dangers
of land-falling tropical storms and hurricanes and urged residents
to stay prepared.
"Every home, school, office,
church or business along the East [and Gulf] Coasts should have
a NOAA Weather Radio, and be prepared to respond when the warnings
are announced," Kelly said.
Tom C. Peterson, chief of the Scientific Services Division at
NOAA's National Climatic
Data Center, said, "If we look at the year-to-date,
January - August period, we find that the U.S. temperature is
at record levels, though only slightly above the 1934 value."
He added, "This is the 17th time the January-August period
for the U.S. was above average in the last 20 years."
Relevant Web Sites
National Weather Service
NOAA's Fire Weather
NOAA's Drought Information
National Climatic Data Center, Asheville, North Carolina
Climate Prediction Center
NOAA's Weather Page
Carey, NOAA's National
Weather Service, (301) 713-0622 or Carmeyia
Gillis, NOAA's Climate
Prediction Center, (301) 763-8000, ext. 7163