National Climatic Data Center

The National Climatic Data Center is a division of the U.S. Department of Commerce that "has a statutory mission to describe the climate of the United States and NCDC acts as the Nation's Scorekeeper regarding the trends and anomalies of weather and climate." 

Contact details
National Climatic Data Center Federal Building 151 Patton Avenue Asheville NC 28801-5001 Phone: 828-271-4800 Fax: 828-271-4876 Web: http://www.ncdc.noaa.gov/oa/ncdc.html