NCDC added Alaska climate divisions to its nClimDiv dataset on Friday, March 6, 2015, coincident with the release of the February 2015 monthly monitoring report. For more information on this data, please visit the Alaska Climate Divisions FAQ.
Maps and Graphics:
PLEASE NOTE: All temperature and precipitation
ranks and values are based on
preliminary data. The ranks will change when the final data
are processed, but will not be replaced on these pages. Once
available, graphics based on final data will be provided on the
Climate Monitoring Products
For graphics covering periods other than those mentioned above or
for tables of national, regional, and statewide data from
1895-present, for March, last 3 months or other periods, please go
to the Climate At A Glance
For information on local temperature and precipitation records
during the month of April, please visit NCDC's Extremes page.
- For the contiguous U.S., last month's average temperature was
51.7°F (10.9°C), which was only 0.3°F (0.2°C)
below the 20th century mean (based on preliminary data). The April
temperature one year ago was the 2nd warmest on record, and the
warmest April occurred in 1981, when the average temperature was
56.1°F (13.4°C). The coldest April occurred in 1920.
- The month will be remembered most for the record cold outbreak
that lasted from April 4-10, producing widespread losses of fruit
crops and damages to trees as far north as southern Illinois, as
far west as Kansas and Texas, and encompassing all the southeastern
states except mid-to-south Florida.
- The lengthy duration of the cold outbreak, the large number of
hours that remained below freezing, and strong winds in many areas,
contributed to crop losses that could reach into the billions of
dollars, according to agricultural experts. The magnitude of the
outbreak is evident in the approximately 900 daily low temperature
records that were set from April 6-9 alone. Additional information
on the April Record-Setting Cold
Wave is available.
- The damaging effects of the record cold were made worse by
record and near-record warmth in March that helped induce an
earlier spring blossom, in some cases two weeks prior to crop
development in 2006. For the month of March more than 2,500 daily
record-high temperatures were set in the contiguous U.S., and it
was the 2nd warmest March on record for the contiguous U.S.
- According to NOAA's Air
Resources Laboratory, Atmospheric Turbulence and Diffusion
Division, forest ecosystem impacts from the cold, which killed
vegetation and reduced tree leaf area, included a subsequent
decrease in carbon dioxide uptake and more of the sun's energy
being used for heating the atmosphere instead of evaporating water
from vegetation. Additional information is available.
- The contiguous U.S. as a whole was drier than average in April.
Abnormally dry conditions were widespread throughout the Southeast
and Pacific Northwest, while much wetter than average conditions
stretched along the Eastern Seaboard from Maine to New Jersey.
- These wet conditions in the Northeast were in large part due to
a strong Nor'easter that moved along the East Coast from the
15th-17th. Strong winds caused power outages that affected hundreds
of thousands from South Carolina to Maine, while heavy rainfall
generated flooding in areas of the Mid-Atlantic and Northeast. New
York City had its second-rainiest day ever, with 7.57 inches on the
15th. The record for the heaviest daily rainfall is 8.28 inches set
on September 23, 1882.
- By contrast, drier than average conditions persisted across
much of the Southeast. Precipitation for the first four months of
the year was less than 50% of average in some areas, and severe
drought stretched from western North Carolina and Tennessee to
southern Mississippi by late in the month, with extreme drought
affecting much of northern Alabama.
- Extreme drought in southern Georgia led to one of the largest
wildfires on record for the state, and several fires continued to
burn in early May. Please see the 2007 Fire Season page for more
- The water year (July 1-June 30) in Los Angeles continued to be
the driest on record and severe to extreme drought stretched from
the southern California coast to Arizona and north along the Sierra
Nevada Mountains, where seasonal snowpack was less than 50% of
average. Additional information on drought conditions is available
For additional details, see the Monthly and
Seasonal Highlights section below and visit the April Climate Summary page. For details and
graphics on weather events across the U.S. and the globe
please visit NCDC's Global Hazards
- Across the United States, extreme drought conditions were
observed in areas of Wyoming and Nebraska, as well as northern
Minnesota and throughout much of the Desert Southwest and the
Southeast region. For more information on drought during April,
please visit the U.S. Drought
- El Niño-Southern Oscillation (ENSO) conditions are in a
ENSO-neutral state. Sea-surface temperatures (SST) anomalies were
near- or below-average across the equatorial Pacific in April.
Current forecasts indicate that a transition from ENSO-neutral
conditions to La Niña could occur over the next 3 months. For
additional information on ENSO conditions, please visit the
NCDC ENSO Monitoring page and
NOAA ENSO Advisory.
Monthly and Seasonal Highlights:
|For additional national, regional, and
statewide data and graphics from 1895-present, for April, the last
3 months or other periods, please visit the Climate At A Glance page.
- April Temperature: 47th
coldest April in the 1895-2007 record. The preliminary
nationally averaged temperature was 51.73°F (10.96°C),
which was 0.31°F (0.17°C) below the 1901-2000 (20th
- April Precipitation:
30th driest nationally in the 1895-2007 record. An average of 2.09
inches (53 mm) fell over the contiguous U.S. in April, 0.34 inches
(9 mm) below the 20th century mean for the month.
- February - April Temperature
(3-Month): 25th warmest in the 1895-to-present record,
1.25°F (0.69°C) above the 20th century mean. The
preliminary nationally averaged February - April temperature was
- February - April Precipitation
(3-month): A total of 5.82 inches (148 mm) of precipitation
fell during this 3-month period, which corresponds to a ranking of
- November - April (6-month):
The national average temperature was the 13th warmest for this
6-month period. The nationally-averaged temperature was
41.04°F (5.02°C), which was 1.68°F (0.93°C)
above the 20th century mean. At 12.82 inches (326 mm), November -
April precipitation was below average and ranked as the 37th driest
such period in the 1895-2007 record.
- January to April
(Year-to-date): The 28th warmest January - April on record. The
nationally averaged year-to-date temperature was 41.18°F
(5.10°C), or 1.14°F (0.64°C) above the mean. The
year-to-date period was the 14th driest January - April in the
113-year record, receiving a national average of 7.96 inches (202
mm) of precipitation during the period, or 1.11 inches (28 mm)
below the 20th century mean.
- May 2006 - April 2007: The
11th warmest such period in the 1895-2007 record. The
preliminary nationally-averaged annual temperature was 54.12°F
(12.29°C), which was 1.31°F (0.73°C) above the mean.
Precipitation for the May 2006 - April 2007 period ranked as the
45th driest May to April in the 112-year record. The
nationally-averaged annual precipitation accumulation was 28.71
inches (729 mm), or 0.43 inches (11 mm) below the 20th century
Other Statewide and Regional
- Following its 3rd coldest March since statewide records began
in 1918, Alaska
had its 4th warmest April on record, with a temperature 5.96°F
(3.3°C) above the 1971-2000 average.
- April temperatures for
ranked 7th coldest. Three other states, including Oklahoma
, and Arkansas
, had much below normal temperatures. Precipitation across Tennessee
was 9th driest on record. New
Jersey and Rhode
Island were 2nd wettest and Massachusetts
were 4th wettest on record.
- February - April temperatures
ranked 7th warmest on record. Five other states, including Utah
were much above average. Alabama,
, and Tennessee
ranked 1st driest for the February - April period.
- The Southeast region, ranked
2nd driest for the February - April period.
- Temperatures over the past 6-months (November - April) were above
average in the all regions except the South, which was near normal.
Precipitation for the period was 6th driest in the West
- November - April temperatures
were much above average for three states, Wyoming, Wisconsin and
New Jersey. Tennessee
ranked 3rd driest for the period, while Nebraska
experienced its 4th wettest such period on record.
- During the Year-to-Date period
(January - April), temperatures were near average to above
average in all states except Texas
ranked 2nd driest for the period.
- January - April
precipitation across the Southeast and West regions was much below
- May 2006 - April 2007 was
near average, warmer or much-warmer-than-average for the lower 48
Hampshire were record wettest for the period.
See NCDC's Monthly
Extremes web-page for weather and climate records for the month
PLEASE NOTE: All of the temperature and precipitation
ranks and values are based on
preliminary data. The ranks will change when the final data
are processed, but will not be replaced on these pages.
Graphics based on final data are available on the Climate Monitoring Products
Citing This Report
NOAA National Climatic Data Center, State of the Climate: National Overview for April 2007, published online May 2007, retrieved on May 25, 2015 from http://www.ncdc.noaa.gov/sotc/national/200704.