National Map Seamless Server
The National Map Seamless Server is the ultimate location to explore and retrieve data. U.S. Geological Survey (USGS) and the EROS Data Center (EDC) are committed to providing access to geospatial data through The National Map. An approach is to provide free downloads of national base layers, as well as other geospatial data layers.
USGS Water Oriented Data Sources
NWS GIS Data Server
National Weather Service GIS
The National Weather Service produces several data sets that are available in formats available to import into Geographic Information Systems (GIS). GIS is a collection of computer hardware, software, and geographic data for capturing, managing, analyzing, and displaying all forms of geographically referenced information. It takes the numbers and words from the... More
Esri ArcGIS Online
ESRI ArcGIS Online
Build public-facing or business solution-focused applications quickly by leveraging the ArcGIS Web Mapping APIs along with content from ArcGIS Online. Included are map and task services, content sharing capabilities, and a range of other online resources such as API samples and references, and code galleries.