2012 Almost Certain to Be Warmest on Record

This photo from NASA's Suomi NPP satellite shows the Eastern Hemisphere of Earth in "Blue Marble" view. The photo, released Feb. 2, 2012, is a companion to a NASA image showing the Western Hemisphere in the same stunning detail. This photo was taken on Jan. 23. CREDIT: NASA/NOAA View full size image

It appears all but guaranteed that 2012 will be the warmest year on record for the continental United States, NOAA's National Climatic Data Center announced Thursday (Dec. 6).

Only a freak cold spell could set this year's national average off its record-breaking course, according to the National Oceanic and Atmospheric Administration (NOAA). Temperatures this month would have to be more than 1.0 degree F (0.55 degrees C) chillier than the coldest-ever December for the 2012 average to miss its record-high target. The coldest December on record occurred in 1983, when the nation's average temperature dipped to 25.54 degrees F (minus 3.59 degrees C).

So far this year, the average national temperature was 57.1 degrees F (13.9 degrees C) through November, marking the warmest first 11 months of any year on record. That's also 3.3 degrees F (1.8 degrees C) above the 20th-century average for the January-November period, and 1.0 degree F (0.55 degrees C) above the previous record set for those 11 months in 1934. Such records have been kept since 1895.

Last month tied November 2004 for the 20th-century warmest November on record, led by warmer-than-average conditions in the western half of the country.

It was also the eighth driest November. The climate report indicated that over 62 percent of the contiguous United States was in a state of drought as November came to a close.

The current record for the warmest year in the Lower 48 was set in 1998, with an average of 54.3 degrees F (12.4 degrees C).

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