|
NOAA scientists report that the
average temperature for the contiguous United States for December,
based on preliminary data, was 35.7 F (2.1C), which was 2.2 F (1.2
C) above the 1895-2003 mean. This was the 23rd-warmest December on
record. The mean temperature in 19 states was above average, with
all but one (New Hampshire) of those states being west of the
Mississippi River. Three western states (Montana, Wyoming, Nebraska)
were much warmer than the long-term mean, while only two states in
the contiguous United States (Mississippi, Louisiana) were cooler
than average for the month.
The relatively warm temperatures for
the nation led to below-normal heating degree days and below-average
residential energy demand. The nation's Residential Energy Demand
Temperature Index was the 35th-lowest on record for December.
The December temperature ranking of
23rd-warmest is close to that for all of 2004 as a whole, which
ended as the 24th-warmest year on record.
Alaska was warmer than average for
December, with a statewide temperature of 4.5 F (2.5 C) above the
1971-2000 mean. The year as a whole was much warmer than average for
Alaska, ranking as the fourth-warmest since statewide records began
in 1918.
December precipitation was near
average for the nation overall; however, dryness in the central part
of the country balanced above-average wetness in the Southwest and
Northeast.
The last few months of 2004 and the
year as a whole were much wetter than average, with the year ending
as the sixth-wettest on record. The latter half of 2004 ranked
second-wettest for any July-December in the last 110 years, partly
as a result of multiple land-falling tropical systems and
much-above-average rain and snowfall in areas of the Southwest.
The wetter-than-average conditions
in parts of the West in 2004 helped alleviate drought that has been
entrenched for more than five years in some western locations.
Although hydrological deficits still remain in much of the West,
moderate-extreme drought affected only 10 percent of the western
United States at the end of December, based on a widely used measure
of drought, the Palmer Drought Index. This compares with 69 percent
in March of 2004, the peak of the 2004 drought.
After a relatively slow start to the
2004-05 winter season for many parts of the country, a major
snowstorm affected much of the Midwest in late December, causing
major disruptions throughout the region. Some cities in the Midwest
received more than their annual average snowfall in a single day.
Residents in cities such as Paducah, Ky., and Evansville, Ind., had
snow totals exceeding a foot, with over 2 feet being reported in
places such as Scottsburg, Ind., and across a large area of the
western Ohio Valley. Snowfall was also recorded in Brownsville,
Texas, for the first time since February 1895, with 1.5 inches
falling on Christmas Day. Farther north, Victoria, Texas, received
over a foot of snow from the same storm, a record for the city.
[to top of second column in
this article] |
The average global temperature
anomaly for combined land and ocean surfaces during December 2004,
based on preliminary data, was 0.79 F (0.44 C) above the 1880-2003
long-term mean. This was the fifth-warmest December since 1880, the
beginning of reliable instrumental records.
Although land-surface temperatures
were anomalously warm throughout Europe, Scandinavia and western
North America, cooler-than-average conditions were widespread across
eastern and northern Canada as well as much of Asia.
Weak El Niņo conditions persisted
into December, with sea-surface temperatures in much of the central
and east-central equatorial Pacific remaining warmer than average
for the month, and the December global ocean-surface temperature was
second-warmest on record.
The warmer-than-average December
concludes another much-warmer-than-average year for the globe:
fourth-warmest since 1880.
NOAA's Satellite and Information
Services is America's primary source of space-based oceanographic,
meteorological and climate data. It operates the nation's
environmental satellites, which are used for ocean and weather
observation and forecasting, climate monitoring, and other
environmental applications. Some of the oceanographic applications
include sea-surface temperature for hurricane and weather
forecasting and sea-surface heights for El Niņo prediction.
NOAA, an agency of the U.S.
Department of Commerce, is dedicated to enhancing economic security
and national safety through the prediction and research of weather
and climate-related events and providing environmental stewardship
of the nation's coastal and marine resources.
On the
Web:
[National
Oceanic and Atmospheric Administration news release] |
