The WRF-NMM model is a fully compressible, nonhydrostatic model with a hydrostatic option (Janjic 2003). Its vertical coordinate is a hybrid sigma-pressure coordinate. The grid staggering is the Arakawa E-grid. The model uses a forward-backward scheme for horizontally propagating fast waves, implicit scheme for vertically propagating sound waves, Adams-Bashforth scheme for horizontal advection, and Crank-Nicholson scheme for vertical advection. The same time step is used for all terms. A number of first and second order quantites, including energy and enstrophy, are conserved.

The WRF-NMM model code contains an initialization program (real_nmm.exe) and a numerical integration program (wrf.exe). The WRF-NMM model Version 3 supports a variety of capabilities. These include:

- Real-data simulations
- Full physics options
- Non-hydrostatic and hydrostatic (runtime option)
- One-way and two-way static nesting
- Applications ranging from meters to thousands of kilometers


Software Requirements

Required libraries (WRF and WPS)

    • FORTRAN 90/95 and c compiler
    • C compiler
    • Perl
    • NetCDF
    • NCAR Graphics (optional but recommended)

Optional libraries for GRIB2 support (WPS)

    • JasPer
    • PNG
    • zlib

Program Flow

In order to run Real Data Cases you will need to run the following programs:

WRF Preprocessing System (WPS) + WRF-NMM Model + WRF Postprocessor (WPP) or RIP



User's Guide
The OnLine Tutorial is complementary to the User's Guide. The User's Guide is updated for every WRF Tutorial and is, therefore, the most up-to-date guide for running the WRF-NMM model. It is highly recommended to download this guide before you start running the model.

WRF Tutorial Presentations
All the slide shows presented at the last WRF Tutorial Class (which used WPS).

Also browse the WRF-NMM Users Page for more information and documentation.