Summer Temperature Highlights
- For summer 2007 (June-August), the average temperature for the
continental U.S. was 73.8°F (23.2°C), which was
1.7°F (1.0°C) above the 20th century mean and the sixth
warmest summer since national records began in 1895, based on
preliminary data.
- This was the warmest summer for Utah and Nevada, and one of the
10 warmest summers on record for 11 other states. Only Texas and
Oklahoma were cooler than average.
- While temperatures in the heavily populated Northeast were near
average, the much warmer than average conditions in the Southeast
and throughout the West led to above average residential energy
demand for the nation. Using the Residential Energy Demand
Temperature Index (REDTI - an index developed at NOAA to relate
energy usage to climate), the nation's residential energy demand
was approximately 8 percent higher than what would have occurred
under average climate conditions for the season.
August Temperature Highlights
- For the contiguous United States, the average temperature for
August was 75.4°F (24.1°C), which was 2.7°F
(1.5°C) above the 20th century mean and the second warmest
August on record, based on preliminary data.
- A severe heat wave persisted throughout much of the month
across southern and central parts of the nation. More than 30
all-time high temperature records were
tied or broken and more than 2000 new daily high temperature
records were established.
- Raleigh-Durham, NC equaled its all-time high of 105°F
(40.6°C) on August 21, and Columbia, SC had 14 days in August
with temperatures over 100°F (37.8°C), which broke the
record of 12 set in 1900.
- The warmest August in
the 113-year record occurred in eight eastern states (West
Virginia, Kentucky, Tennessee, the Carolinas, Georgia, Alabama, and
Florida) along with Utah. For the Southeast, the length, severity
and area of the heat wave led to comparisons with events in 1983
and 1954. The nation's August REDTI was the highest August value in
113 years and was 16 percent above the mean energy consumption for
the month. Alaska was 3.28°F (1.82°C) warmer than the
1971—2000 mean in August.
Summer Precipitation Highlights
- The summer was drier than average for the nation as a whole.
Rainfall was below average in the Southeast, mid-Atlantic, and Ohio
Valley as well as the northern Plains and Northern Rockies.
- A persistent atmospheric pattern brought much
drier-than-average conditions to the Southeast and much
wetter-than-average conditions to the South region. Texas had its
wettest summer on record and Oklahoma its 4th wettest. In the
Southeast, this was the driest summer since records began in 1895
for North Carolina and the second driest for Tennessee.
- A hot and dry July in the northern Rockies contributed to a
fast start to the wildfire season, and August remained very active
as warmer and drier-than-average conditions persisted in many
areas. By early September, more than 7 million acres had burned
across the nation, most of it in the western U.S.
August Precipitation Highlights
- The record warmth and below average rainfall of August led to
an expansion of drought in the Southeast and parts of the
mid-Atlantic and Ohio Valley. At the end of August drought affected
approximately 83% of the Southeast region and 46% of the contiguous
U.S., according to the federal U.S. Drought Monitor.
- Severe drought persisted throughout much of the West as well as
an area that stretched from northern Minnesota to the Upper
Peninsula of Michigan.
- Sandwiched between drought to the north and south, the central
third of the Midwest received record precipitation in August as a
persistent frontal system provided a focus for heavy rain and
thunderstorms. Precipitation was two to three times normal for the
month in a wide band across the central Midwest, where Iowa had its
wettest August on record. Only 10 to 25 percent of normal
precipitation amounts fell in southwestern Kentucky and less than
25 percent of normal fell in Michigan's Upper Peninsula.
Other Items of Note
- Many areas in Tennessee, Alabama, Mississippi, Arkansas,
Georgia, and South Carolina had more than ten days of triple digit
temperatures in August. It was, by far, the hottest month on
record in Tennessee, and the average high temperature for the month
was a remarkable 82.9°F (28.3°C), more than 6.6°F
(3.7°C) above the monthly average and more than 2.8°F
(1.6°C) above the previous record set in 1936. More
information about the exceptional heat in August can be found at
the special August heat wave
page.
- Drought severity worsened during the month of August in the
Central and Southeast regions and in parts of Montana, Idaho, and
northern Wisconsin and Minnesota, the northern plains, the Midwest,
and the mid-Atlantic. The most severe drought in the nation was
concentrated in a large portion of Alabama, Mississippi, Kentucky,
Tennessee, Georgia, Florida, the western Carolinas, and in small
portions of Arkansas, Virginia, and Ohio. Extreme drought
conditions also persisted or intensified in the southwestern states
of Arizona, California and Nevada, as well as in Idaho, Montana,
Wyoming, South Dakota, Nebraska, Minnesota, Wisconsin, and the
Upper Peninsula of Michigan. For more information on drought during
August, please visit the U.S. Drought
Watch page.
- In the tropical Pacific Ocean, La Niña conditions were
developing. By the end of August, sea-surface temperature (SST)
anomalies remained positive in the western equatorial Pacific and
became more negative in the eastern equatorial Pacific. Most
dynamical models are forecasting the strengthening of the La
Niña conditions in the next couple of months, while some
statistical models are forecasting the return of El Niño
Southern Oscillation (ENSO)-neutral conditions. A developing La
Niña may result in wetter than normal conditions in the
Pacific Northwest and drier than normal conditions in the
southwestern U.S. in the fall. For additional information on ENSO
conditions, please visit the NCDC
ENSO Monitoring page and the latest
NOAA ENSO Advisory.
For additional details about recent temperatures and
precipitation across the U.S., see the Monthly and
Seasonal Highlights section below and visit the August Climate Summary page. For
information on local temperature and precipitation records during
the month of August, please visit NCDC's Extremes page. For details and graphics on
weather events across the U.S. and the globe please visit
NCDC's Global Hazards page.
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