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National Overview - April 2007


NCDC transitioned to the nClimDiv dataset on Thursday, March 13, 2014. This was coincident with the release of the February 2014 monthly monitoring report. For details on this transition, please visit our public FTP site and our U.S. Climate Divisional Database site.

Maps and Graphics:


April Most Recent 3 Months Most Recent 6 Months
Most Recent 12 Months Year-to-Date US Percent Area Very Wet/Dry/Warm/Cold
Annual Summary for 2006

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 page.


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 page.
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National Overview:


April
  • 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 information.

  • 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 here.

For information on local temperature and precipitation records during the month of April, please visit NCDC's Extremes page.

  • 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 page.

  • 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 the latest NOAA ENSO Advisory.
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 page.
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Monthly and Seasonal Highlights:


Contiguous U.S.:

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 century) mean.

  • 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 44.35°F (6.86°C).

  • 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 11th driest.

  • 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 mean.

Alaska:
  • 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.

Other Statewide and Regional Highlights:

See NCDC's Monthly Extremes web-page for weather and climate records for the month of April.

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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 page.

Citing This Report

NOAA National Climatic Data Center, State of the Climate: National Overview for April 2007, published online May 2007, retrieved on April 19, 2014 from http://www.ncdc.noaa.gov/sotc/national/2007/4.