The 2006 average annual temperature for the contiguous U.S. was the warmest
on record and nearly identical to the record set in 1998, according to scientists
at the NOAA National Climatic Data Center in Asheville, N.C. Seven months in
2006 were much warmer than average, including December, which ended as the
fourth warmest December since records began in 1895.

Based on preliminary data, the 2006 annual average temperature was 55
degrees F—2.2 degrees F (1.2 degrees C) above the 20th Century mean and
0.07 degrees F (0.04 degrees C) warmer than 1998. NOAA originally estimated
in mid-December that the 2006 annual average temperature for the contiguous
United States would likely be 2 degrees F (1.1 degrees C) above the 20th Century
mean, which would have made 2006 the third warmest year on record, slightly
cooler than 1998 and 1934, according to preliminary data. Further analysis of
annual temperatures and an unusually warm December caused the change in
records.

For the complete report click the link below:
 http://www.noaanews.noaa.gov/stories2007/s2772.htm