|Dec-Feb land and ocean surface mean temperature anomalies. Click to enlarge.|
The December 2006-February 2007 global average temperature was the warmest since 1880—(1.30°F/0.72°C above the 20th century mean)—according to scientists at the US National Oceanic and Atmospheric Administration (NOAA).
The global December-February land-surface temperature was the warmest on record, while the ocean-surface temperature tied for second warmest in the 128-year period of record, approximately 0.1°F (0.06°C) cooler than the record established during the very strong El Niño episode of 1997-1998.
During the past century, global surface temperatures have increased at a rate near 0.11º F (0.06º C) per decade, but the rate of increase has been three times larger since 1976, or 0.32ºF (0.18ºC) per decade, with some of the largest temperature increases occurring in the high latitudes of the Northern Hemisphere.
Temperatures in the US for the winter season were slightly above average—33.6°F (0.9°C), compared to the 20th century average of 33.0°F (0.6°C).
Statewide temperatures were warmer than average from Florida to Maine and from Michigan to Montana. Cooler-than-average temperatures occurred in the southern Plains and areas of the Southwest.
February was 1.8°F (0.9°C) below the 20th century average of 34.7°F (1.5°C), placing it in the top third coldest Februarys in the 113-year record for the contiguous US. Thirty-six states in the eastern two-thirds of the nation were cooler than average, while Texas and the eleven states of the West were near average to warmer-than-average.
|Palmer drought index. Click to enlarge.|
Winter precipitation was above average from the Upper Midwest to New Mexico, Texas and Louisiana. Winter was drier than average from the Deep South to Kentucky, the Mid-Atlantic, and along the Northeast Seaboard states. Much of the West was also drier than average. For February, precipitation was below average in the Southeast, Northeast and Midwest regions.
At the end of February, water-year precipitation in Los Angeles was the lowest on record, less than 25% of normal. According to the US Drought Monitor, 25% of the continental US was in moderate-to-exceptional drought at the end of February. The most severe conditions were in southwest Texas, northern Minnesota, Wyoming and the western High Plains.