National Weather Service (NWS) Advanced Hydrologic Prediction Service (AHPS)
AHPS is a web-based suite of accurate and information-rich forecast products. They display the magnitude and uncertainty of occurrence of floods or droughts, from hours to days and months, in advance. An interactive map allows users to view current observations and forecasts.
The majority of the observed water level data displayed on the AHPS web pages originates from the United States Geological Survey's (USGS) National Streamflow Information Program which maintains a national network of streamgages. In addition, real-time water level information is collected from other federal, state, and local streamgage networks.