"National Water Conditions"/current streamflow data for the U.S. and southern Canada, provided by the USGS in collaboration with the Climate Information Branch of Environment Canada, is found at
The Climate Prediction Center of the National Centers for Environmental Prediction engages in short-term climate predictions, which involves considering historic climate trends. Historic precipitation data, U.S. and foreign, can be accessed via links at
NASA, in collaboration with the National Space Development Agency of Japan, is developing better methods of monitoring rainfall in tropical and subtropical regions, which has both streamflow and water-resource implications. The Tropical Rainfall Measuring Mission site is at