From the NCEI:
We’ve updated the U.S. Climate Atlas and created a new interface to provide you easier access to it.
Unlike the previous version, which was only available on CD-ROM, the new Atlas is available through an interactive website that you can freely access anywhere there’s an internet connection. With the website, you can view, compare, or animate monthly maps of precipitation and maximum and minimum temperatures from 1895 through 2015.
We made the U.S. Climate Atlas maps with weather observations included in our 120-year-long nClimDiv dataset from over 10,000 stations. The Atlas also includes “climatology” maps that we generated with the 1981–2010 Climate Normals. These Normals represent “typical” or “average” conditions, and our scientists calculate them every 10 years.
Overall, the U.S. Climate Atlas and its maps show temperature and precipitation patterns at both regional and national levels. You can also use these maps to study historical heat waves, cold waves, floods, and droughts. And, you can easily download and save all of the maps from the website.
Direct to National Climate Atlas