WRF Release Information

Latest Release

The latest WRF system major release is Version 4.0 (June 2018).  While details on it may be found at WRF V4.0: Updates and WRF Downloads, some of V4.0's major improvements are as follows.

  • Dynamics: Hybrid vertical coordinate as default, theta-m prognostic temperature variable as default
  • Software: Default compression and netCDF4, computation of model vertical levels with smooth dz variation
  • Physics: Updated Thompson-Eidhammer aerosol-aware and P3 microphysics schemes, updated Smirnova LSM, new KSAS cumulus scheme, crop model added to Noah-MP LSM, RTTMG-K radiation package, MYNN PBL and surface layer scheme updates
  • WRFDA: GOES imager radiance assimilation, addition of GPSRO Excess Phase observation operator, addition of analysis constraint and divergence constraint
  • WRF-Chem: PV-based stratospheric ozone calculation, MOSAIC-II scheme, MOZART-T1 scheme, new Henry's Law constant table, new heterogeneous gas chem option
  • WRF-Fire: Parallelization of level-set method algorithm
  • HWRF: Addition of 2017 operational system modifications

Fixes for issues identified in V4.0 will be done via provision of the WRF repository with open development status on github.


Future Release— WRF V4.1

The next major WRF release will be Version 4.1 and is targeted for Spring 2019.  A list of specific candidate features will be posted after the release preparation begins, and will appear here in Fall 2019.  As always, the ultimate inclusion of any candidate item is dependent on its timely preparation and acceptance.

  • Software: Resolution of reported issues in V4.0.
  • Physics: Resolution of reported issues in V4.0.

Developers seeking to propose code for new or improved capabilities for the WRF system must review Information for Code Contributors. The consideration of any code for inclusion in the WRF repository or a release depends on the developer's following the physics review procedures, meeting testing preparation and documentation requirements, and adhering to the release schedule. Prospective contributors may post to the WRF & MPAS-A Support Forum http://forum.mmm.ucar.edu/phpBB3/ for information and for contacting the Developers' Committee (which oversees WRF contributions and manages the repository) or the Release Committee (which oversees the major release process). Both the Developers' Committee and the Release Committee are described in WRF Code Repository and Release Administration.


2019 WRF Major Release Timeline

The timeline for the next major WRF release, V4.1, scheduled for late Spring 2019, is as follows. "RC" refers to the Release Committee; "DC" refers to the Developers' Committee.

September 2018

  • RC begins meetings for major release cycle.
  • Initial release picture compiled and schedule set.

January 2019

Code accepted and admitted to the repository is eligible to be included in the release. Code submissions must undergo all preliminary testing and acceptance by this time in order to be considered for the release. A release branch of the code is designated and becomes the basis for the release. While the WRF repository will remain open to submissions, new additions will not be eligible for the release branch.

February-March 2019

Release code testing and first friendly-use release

  • Only bugfixes for preliminary release code permitted.
  • WRF repository remains open for code additions, which may be considered for releases after the major release.
  • Friendly-user releases— preliminary code made available for testing.

March-April 2019

  • Continued release code testing by friendly users.
  • Resolution of reported issues in the preliminary code.
  • Full set of regression tests run on machines at NCAR.

April 2019

  • Final round of troubleshooting and large testing.
  • RC and DC meetings focus on remaining code needs and testing. Final code commits.
  • DC certifies code for release. Code packaged and staged for release.
  • Release of V4.1 and user notification.

Release Committee

The WRF Release Committee oversees the major releases of WRF. It is described in the policies for NCAR's administration of the WRF code in WRF Code Repository and Release Administration. The members are listed below.

Jordan Powers, NCAR/MMM— Chairman
Ravan Ahmadov, NOAA/ESRL
Michael Barlage, NCAR/RAL
Laurie Carson, DTC
Jimy Dudhia, NCAR/MMM
Dave Gill, NCAR/MMM
Jake Liu, NCAR/MMM
Wei Wang, NCAR/MMM