National Water Model

The National Water Model is a water forecasting model operated by the NOAA National Weather Service that continually forecasts flows on 2.7 million stream reaches covering 3.2 million miles of streams and rivers in the continental United States. It operates as part of the national weather forecasting system and is directly connected to outputs from its numerical weather prediction models, and to weather and water conditions observed throughout the continental US, including the US Geological Survey National Water Information System. The National Water Model became operational in August 2016 as a prototype system, and is currently undergoing extensive validation and verification to identify where scientific updates to the model can make the most improvement.

The purpose of this information page is to provide links to information about the National Water Model and the technical foundation on which it has been constructed.

1. Information from NOAA

NOAA National Water Model web interface provides point and click real-time forecast information from stream reaches

General description of National Water Model

National Water Model Experimental Image Viewer

This FTP site provides free access to all National Water Model output for the most recent two days.

Announcement about National Water Model Version 2.0 NWMVer2_0.pdf

Coverage of 2.68 million NWM Forecast Points (centroid of NHDPlus Reaches)

National Water Model reanalysis data, 1993 to 2018

Google NWM Archive: all forecasts output since Sept 17, 2018 

Integrated Water Resources Science and Services (IWRSS)

Design for the National Flood Inundation Mapping Services


2. Information from NCAR

The National Water Model uses a technical framework called WRF-Hydro (Weather Research and Forecasting Model-Hydro) to link weather and hydrological forecasting that is developed and maintained at the National Center for Atmospheric Research. WRF-Hydro is described at:

3. Information from CUAHSI

Rapid prototyping to develop and enhance the National Water Model is being carried out by the US academic community, coordinated by the Consortium of Universities for the Advancement of Hydrologic Science, Inc (CUAHSI). The collaboration between the National Weather Service and CUAHSI was initially launched in 2015 as a National Flood Interoperability Experiment:
Conceptual Framework of the National Flood Interoperability Experiment

A NOAA National Water Center Innovators program has sponsored a program of Summer Institutes, organized through CUAHSI, and held annually at the National Water Center on the Tuscaloosa campus of the University of Alabama. So far, a total of 105 graduate students from 49 universities have participated in these Summer Institutes.

Summary Report from 2016 Summer Institute

Summary Report from 2017 Summer Institute

4. Information from AWRA

Publications of the American Water Resources Association (AWRA) have served as an information source for the National Water Model and the research supporting its development.

Water Resources Impact: National Water Model

5. Information from ESRI

The Environmental Systems Research Institute (ESRI), continually publishes water forecast maps from the National Water Model as part of its Living Atlas. Login to, add data from Living Atlas and search for layers of title National Water Model.

Flood impact calculator

6. HAND Flood Mapping

HAND 10m inundation map database:


Flood Frequency Estimates from NWM Reanalysis Version 2.0 FFA_NWM_V2.xlsx The values given are in cfs and are produced by a Bulletin 17B frequency analysis of the National Water Model reanalysis data from NWM Version 2.0.


Papers about HAND


7. Pin2Flood Application

Field App -

EOC App -

One Pager Pin2FloodOnePager.pdf

Data Flow Pin2FloodData.pdf

7. TxDOT Flow Measurement Project

TxDOT Bridge Portal:


Kisters Sites Story Map:


Project Sites Story Map


Depth Error at USGS sites

Box Data Site

8. TCEQ Water Operations Models



9. Oak Ridge National Lab Building Structures