This site maintains a database of annual and 24 hour rainfall maximums and minimums by state, available in table or map form. It also contains records of specific events including hurricanes, El Nino and extreme storms for the past ten years. Full description.

The United States Geological Survey maintains a series of streamflow-gauging stations across the United States. This site provides a map of current water levels across the United States, and lets the user access continuous records of river stages from hundreds of stations across the country. These data are recorded and broadcast at approximately 15 minute intervals via satellite telemetry systems. ... Full description.

The National Weather Service maintains this small series of flooding accounts. The listings include important information on the antecedent conditions in the area of flooding. Most major northeastern floods from the time period of 1927 to the present are discussed. Though the number of examples is small, they represent a diversity of flood conditions and are useful for understanding the critical conditions ... Full description.

This site provides access to water use reports for the country and by county and watershed at five year intervals from 1950 to 2000. There is also a region by region comparison and information about how the data was collected. Full description.

This is a huge collection of maps showing vegetation around the world. World, regional, and country maps are available. Full description.