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.