2012 was warmest and second most extreme year on record for the
contiguous U.S.
2012 was a historic year for extreme weather that included
drought, wildfires, hurricanes and storms; however, tornado activity was
below average
2012 marked the warmest year on record for the contiguous United
States with the year consisting of a record warm spring, second warmest
summer, fourth warmest winter and a warmer-than-average autumn. The
average temperature for 2012 was 55.3°F, 3.2°F above the 20th
century average, and 1.0°F above 1998, the previous warmest year.
The average precipitation total for the contiguous U.S. for 2012 was
26.57 inches, 2.57 inches below average, making it the 15th
driest year on record for the nation. At its peak in July, the drought
of 2012 engulfed 61 percent of the nation with the Mountain West, Great
Plains, and Midwest experiencing the most intense drought conditions.
The dry conditions proved ideal for wildfires in the West, charring 9.2
million acres — the third highest on record.
The U.S. Climate Extremes Index indicated that 2012 was the second
most extreme year on record for the nation. The index, which evaluates
extremes in temperature and precipitation, as well as landfalling
tropical cyclones, was nearly twice the average value and second only to
1998. To date, 2012 has seen 11 disasters that have reached the $1
billion threshold in losses, to include Sandy, Isaac, and tornado
outbreaks experienced in the Great Plains, Texas and Southeast/Ohio
Valley.
Select 2012 temperature and precipitation extremes
Click image for additional details.
Note: The Annual Climate Report for the United
States has several pages of
supplemental information and data regarding some of the exceptional
events 2012.
U.S. temperature
-
2012 Statewide Temperature (top) ranks
Every state in the contiguous U.S. had an above-average annual
temperature for 2012. Nineteen states had a record warm year and an
additional 26 states had one of their 10 warmest.
- On the national scale, 2012 started off much warmer than average
with the fourth warmest winter (December 2011-February 2012) on
record. Winter warmth limited snow with many locations experiencing
near-record low snowfall totals. The winter snow cover for the
contiguous U.S. was the third smallest on record and snowpack totals
across the Central and Southern Rockies were less than half of
normal.
- Spring started off exceptionally warm with the warmest March on
record, followed by the fourth warmest April and second warmest May.
The season’s temperature was 5.2°F above average, making it easily
the warmest spring on record, surpassing the previous record by
2.0°F. The warm spring resulted in an early start to the 2012
growing season in many places, which increased the loss of water
from the soil earlier than what is typical. In combination with the
lack of winter snow and residual dryness from 2011, the record warm
spring laid the foundation for the widespread drought conditions in
large areas of the U.S. during 2012.
- The above-average temperatures of spring continued into summer.
The national-scale heat peaked in July with an average temperature
of 76.9°F, 3.6°F above average, making it the hottest month ever
observed for the contiguous United States. The eighth warmest June,
record hottest July, and a warmer-than-average August resulted in a
summer average temperature of 73.8°F, the second hottest summer on
record by only hundredths of a degree. An estimated 99.1 million
people experienced 10 or more days of summer temperatures greater
than 100°F, nearly one-third of the nation’s population.
- Autumn and December temperatures were warmer than average, but
not of the same magnitude as the three previous seasons. Autumn
warmth in the western U.S. offset cooler temperatures in the eastern
half of the country. Although the last four months of 2012 did not
bring the same unusual warmth as the first 8 months of the year, the
September through December temperatures were warm enough for 2012 to
remain the record warmest year by a wide margin.
U.S. precipitation
- The nationally-averaged precipitation total of 26.57 inches was
2.57 inches below average and the 15th driest year on
record for the lower 48. This was also the driest year for the
nation since 1988 when 25.25 inches of precipitation was observed.
2012 Precipitation ranks
Each season of 2012 had precipitation totals below the 20th
century average:
- Winter brought below-average precipitation to both coasts
and above-average precipitation to the Southern Plains, slightly
lessening drought conditions that plagued the region in 2011.
The winter precipitation total was 89 percent of normal.
- Spring precipitation was 95 percent of the 20th
century average with below-average precipitation in the Rockies
and Midwest and above-average precipitation in the Northwest and
Upper Midwest.
- Summer precipitation was 88 percent of normal with dry
conditions in the central United States. The West Coast, Gulf
Coast, and Northeast were wetter than average.
- Autumn was drier than average for most of the central U.S.,
with wet conditions in the Northwest, Ohio Valley, and
Northeast. The autumn precipitation total was 85 percent of
average.
Alaska and Hawaii
- Alaska was cooler and slightly wetter than average during 2012.
The year began very cold for the state with a January temperature
14.0°F below the 1971-2000 average. Each subsequent season was also
cooler than average, resulting in an annual temperature 2.3°F below
average. Much of 2012 was also wetter than average, and the annual
precipitation total was 9.2 percent above average.
- Drought conditions continued to plague Hawaii during 2012. At
the beginning of 2012, 47.4 percent of the state was experiencing
moderate-to-exceptional drought, according to the U.S. Drought
Monitor. By the end of the year, the percent area experiencing
moderate-to-exceptional drought expanded to 63.3 percent of the
state.
Significant weather and climate events
- Tropical cyclone activity across the North Atlantic in 2012 as
above-average with 19 named storms, ten hurricanes, and one major
hurricane (Category 3 or stronger). This is the third consecutive
North Atlantic tropical cyclone season with 19 named storms and ties
with as the third most active season for the basin. Isaac and Sandy
made landfall along the U.S. coast during 2012 causing significant
impacts. Isaac brought large storm surge and torrential rains to the
Gulf Coast. Sandy caused significant damage to the Northeast, with 8
million homes losing power and 131 fatalities reported.
- The widespread drought conditions of 2012 peaked in July with
approximately 61 percent of the country experiencing drought
conditions. The footprint of drought during 2012 roughly equaled the
drought of the 1950s which peaked at approximately 60 percent. The
size of the current drought and the drought of the 1950s are smaller
than the drought episodes of the 1930s. The current drought has yet
to reach the intensity or duration of the 1950s and 1930s
national-scale droughts.
- Wildfire activity during 2012 was above-average with 9.2 million
acres burned the third most in the 13-year record. Numerous large
and destructive wildfires impacted the western U.S. throughout the
year. The Waldo Canyon fire near Colorado Springs, Colorado
destroyed nearly 350 homes and was the most destructive fire on
record for the state. The Whitewater-Baldy Complex fire charred
nearly 300,000 acres and was the largest on record for New Mexico.
- Tornado activity during 2012 was below the 1991-2010 average of
approximately 1,200. The year got off to a busy start with large
tornado outbreaks in March and April causing significant damage in
the Ohio Valley and Central Plains. May and June, typically the most
active tornado months of the year, both had less than half of
average tornado counts. The final 2012 tornado count will likely be
less than 1,000 — the least since 2002.
Please see the
NCDC
Contact Page if you have questions or comments.
http://www.ncdc.noaa.gov/sotc/index.php
Created by Jesse.Enloe@noaa.gov
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