National Climatic Data Center (NCDC) is the world's largest active archive of weather data. NCDC produces numerous climate publications and responds to data requests from all over the world. NCDC operates the World Data Center for Meteorology and the World Data Center for Paleoclimatology.
NCDC's geospatial data products are available through the following types of services: dynamic mapping applications, OGC web services (WMS, WFS, KML/KMZ), and Catalog Service for the Web (CS-W).
ESRI recently featured the NCDC Geodata Portal in an article in ArcNews from Spring 2011