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The content provided on this page supports model development. These are not official NWS products and should not be relied upon for operational purposes. This web site is not subject to 24/7 support, and thus may be unavailable during system outages.

Please see our disclaimer for more information.

EMC Operational Wave Models

Here you can find links to model forecast data as well as images generated from the EMC suite of operational wave models. These models are based on the 3rd generation wave model WAVEWATCH III® using operational NCEP products as input.

Global Forecast System - Wave

The Global Forecast System (GFS) is a global numerical weather prediction system containing a global computer model and variational analysis run by the U.S. National Weather Service (NWS).

The model is run four times a day: 00Z, 06Z, 12Z, and 18Z. Each run produces forecasts of every hour from the initial time out to 120 hours, and then forecasts at 3-hour intervals out to 384 hours (the animated image viewer only shows data out to 240 hours).

The coupled wave model consists of global and regional nested grids. As background information, a list of selected references and a chronological list of model changes are available. Finally, GFS-Wave buoy validation is available.

Links to Model Data (FTP) (https) (OpenDAP) (Grib Filter)

* GFS-Wave data is located in gfs.YYYYMMDD/CC/wave (YYYY=year, MM=month, DD=day, CC=cycle (00,06,12,18 Z)

Global Ensemble Forecast System - Wave

The Global Ensemble Forecast System - Wave (GEFS-Wave) is a one-way coupling of the GEFS atmospheric model with the WAVEWATCH III wave model. This allows for an increase in frequency of the wind forcing from 3 hours to 1 hour. This unified system has 30 members and the wave model is initialized with the previous member's 6 hour forecast. The wave model has a spatial resolution of 0.25 x 0.25 degrees. The system runs four cycles per day (00, 06, 12 and 18Z). The wave forecast has been extended from 10 to 16 days.

More information on the GEFS system is available here.

Links to Model Data (FTP) (https) (Grib Filter)

* GEFS-Wave data is located in gefs.YYYYMMDD/CC/wave (YYYY=year, MM=month, DD=day, CC=cycle (00,06,12,18 Z)

Great Lakes Wave

The Great Lakes wave model consists of a single unstructured grid. As background information, a list of selected references and a chronological list of model changes are available.

The model is run four times a day: 00Z, 06Z, 12Z, and 18Z. Each run starts with 9-, 6- and 3-hour hindcasts and produces forecasts of every 3 hours from the initial time out to 84 hours.

Links to images (Animated Image Viewer) (Product Table)
Links to Model Data (FTP) (https) (OpenDAP) (Grib Filter)

* Great Lakes Wave data is located in glwu.YYYYMMDD/CC/wave (YYYY=year, MM=month, DD=day, CC=cycle (00,06,12,18 Z)

NCEP/FNMOC Combined Wave Ensemble

The NCEP/FNMOC Combined Wave Ensembles (NFCENS) product consists of a combination of wave ensemble outputs from the GEFS-Wave ensemble system, and from the wave ensembles run by the US Navy Fleet Numerical Meteorology and Ocenographic Center (FNMOC). The product combines outputs from a total of 51 wave ensemble members: one control run and 30 members from the GEFS-Wave system, and 20 additional members from FNMOC.

Nearshore Wave Prediction System

The Nearshore Wave Prediction System (NWPS) provides on-demand, high-resolution nearshore wave model guidance to U.S. coastal WFOs, triggered in real time by forecast wind grids prepared and submitted by the individual offices. NWPS is maintained and developed by NCEP's Environmental Modeling Center (EMC) in collaboration with a number of Weather Forecast Offices (WFOs), as well as partners at NOAA/NOS, USGS and USACE.

Link to NWPS

Hindcast and Reanalysis Archives

There are two classes of WAVEWATCH III® hindcasts.

  • A thirty-year hindcast generated from the NCEP Climate Forecast System Reanalysis and Reforecast (CFSRR) homogeneous dataset of hourly high-resolution winds. The time period covers from 1979 through 2009. This is a true hindcast generated with a single version of the model and a statistically consistent forcing wind field, and is suitable for use in climate studies.
  • A data set produced by rerunning the model from the operational wind fields to produce best-estimate nowcast datasets for the period Feb 2005 through May 2019. This is a statistically inhomogeneous hindcast data set, because the underlying models are periodically updated. Therefore this data set should not be used for climate studies.

Detailed descriptions of the hindcasts and reanalyses, with links to the datasets, validation statistics from buoy match-ups, and visualizations of the model data fields, can be found in the archive.

WAVEWATCH III® Model Description and GitHub Repository

We have moved to an open development paradigm using GitHub, which means users and developers are no longer required to submit requests for usernames and passwords to access our software package.

The WAVEWATCH III® project page is here.

The latest release is available as a compressed tarball or zipfile from the project page.

To help users and developers navigate the new repositories, we have created two sets of guidelines in GitHub to help you navigate our community modeling framework, one for users and the other for developers:

  • If you are a user and would like to access the code for applications and do not plan to engage in development work, see the User Guide.

  • If you are a developer and would like to add a new feature to the code, see the Developer Guide.

The WW3 GitHub wiki hosts a description of the model, its main features, output options, user and developer guides, technical documentation and latest news.


Two COMET modules are available regarding WAVEWATCH III® and analysis of ocean swell:

Registration is required, but there is no cost for the courses.