The winter of 2011-2012, by the astronomical definition, was the warmest on record in Washington, D.C. according to the National Weather Service.

The average temperature was 45.6 degrees, nearly two degrees above the previous record holder of 1989-90, when the average temperature was 43.7 degrees. Records have been maintained since 1871.

Remarkably, Washington only logged 24 days when temperatures reached 32 or lower, the fewest such days on record.

The astronomical definition of winter typically spans December 21 to March 20, but can vary by a day or two. This year’s astronomical winter began December 22 and ended March 19.

By the meteorological definition of winter, December 1 through February 29, it was the third warmest winter on record in Washington.

The exceptionally warm winter follows a number of other notably warm seasons in Washington in the last two years:

* Astronomical spring in 2010 was the warmest on record

* Meteorological summer in 2010 was the hottest on record

* Astronomical summer in 2010 was the second hottest on record

* Meteorological summer in 2011 was the second hottest on record


July 2011: The hottest month in Washington, D.C. history

Is there a global warming signal in Washington D.C. summer temperatures?

D.C.’s cherry blossoms have shifted 5 days earlier: what about global warming and the future?

Does D.C.’s warm winter mean a hot summer is to follow?