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National Water Model

The National Water Model (NWM) is a hydrologic high resolution model that has the ability to forecast and simulate the rivers and streams flows throughout the entire United States territory. The new National Water Model improves the National Weather Service’s ability to deliver impact-based decision support services nationwide , as well as serve as the foundation for additional private sector water services. Using mathematical representations the NWM simulates the water cycle and it also explains how all the processes fit together. This complex representation of physical processes such as snow-melt and infiltration and movement of water through the soil layers varies significantly with specific factors. Some of which would be the changing elevations, soils, vegetation types. Additionally, extreme variability in precipitation over short distances and times can cause the response on rivers and streams to change very quickly.

The NWM complements current hydrologic modeling which is done in a simplified manner for approximately 4000 locations across the CONUS (continental United States) by providing information at a very fine spatial and temporal scale at those locations, as well as for locations that don’t have a traditional river forecast.

BYU Role

The NWM is currently is not widely used or available. To counter this, The BYU Hydroinformatics lab is creating a HydroServer application. This app will allow users to easily manipulate data from the over 4 million streams and rivers tracked by the National Weather Service. BYU’s goal is to have the NWM quickly accessible to anyone who has need for stream flow data.

Useful Links


Souffront Alcantara, Michael A; Crawley, Shawn; Stealey, Michael J.; Nelson, E. James; Ames, Daniel P.; Jones, Norm L. (2017). Open Water Data Solutions for Accessing the National Water Model. Retrieved from