WRF Working Group 13: Ensemble Forecasting

Update: 5 July 2007

Code is now available to help in generating perturbed initial conditions and scripts for running an ensemble system! Josh Hacker of NCAR has developed several scripts to 1) generate a perturbed set of initial conditions, and 2) to run a multi-model WRF ensemble. The needed Vtables , netcdf file , and scripts are all available.

A second set of scripts and code are being made available to develop a set of perturbed ensemble initial conditions based upon the WRF 3DVAR system. This code was developed by Yongsheng Chen and Chris Snyder at NCAR and has been modified by Nusrat Yussouf of NSSL. Both instructions and code are available.

Lead: David Stensrud
Email: wrf-wg13@wrf-model.org
Website: Working Group 13


Stanley Benjamin, (FSL)
Brian Colle, (SUNY Stonybrook)
Jeffrey Cunningham, (AFWA)
Kelvin Droegemeier, (Univ. Oklahoma)
Tony Eckel, (AFWA)
Brian Etherton, (UNCC)
Rob Fovell, (UCLA)
Josh Hacker, (NCAR)
Tom Hamill, (NOAA)
Pat Hayes, (NGC)
Steve Mullen, (Univ. Arizona)
Nelson Seaman, (NOAA)
Brent Shaw, (WNI)
Chris Snyder, (NCAR)
David Stauffer, (Penn State)
David Stensrud, (NOAA)
Steven Tracton, (ONR)
Xuguang Wang, (NOAA)
Fuqing Zhang, (Texas A&M)


To encourage the development and evaluation of ensemble forecasting systems based upon the WRF model through the sharing of results, techniques, and software, the organization of workshops and tutorials, and the development of collaborative research projects.

Short-term working group goals:

1) Organize ensemble-related scientific workshops and special sessions in the annual WRF workshop specifically targeted at ensemble studies and applications. Specifically, organize a WRF ensemble forecasting tutorial as part of the regular WRF tutorials beginning in 2007 (Josh Hacker, lead).

2) Promote the development of needed tools and their sharing through the WRF ensemble forecasting web page (David Stensrud, lead). Encourage ensemble forecasting working group members to collaborate on proposal submissions.

Longer-term working group goals:

3) Establish testbeds for evaluating ensemble forecasting techniques that would contribute to the optimal design of ensemble systems.

4) Establish better contacts with members in the data assimilation, model physics, and verification working groups.

Information Sharing:

The R package is a very helpful tool to use for verification of ensemble forecasts. This statistical package can calculate ROC diagrams, and help with other probabilistic verification methods. R-website: R-page

The Data Assimilation Research Testbed is presently exploring ensemble Kalman filter techniques with WRF.

Recent Reports of Interest:

NAS Report (2006), "Completing the Forecast: Characterizing and Communicating Uncertainty for Better Decisions Using Weather and Climate Forecasts", http://newton.nap.edu/catalog/11699.html

NAS Report (2003), "Communicating Uncertainties in Weather and Climate Information: A Workshop Summary", http://newton.nap.edu/catalog/10597.html

Those interested in joining this working group should send email to David Stensrud (David.Stensrud@noaa.gov).