WPS Version 3.1.1
              Version 3.1.1 of the WRF Pre-Processing System (WPS)  was released on July 31, 2009. For WRF V3.1.1 update, click here. 
              New features and bug fixes 
              - Added configuration option for ifort compiler on Intel-based Macs
                - Fix to allow ungrib to be compiled on systems with case-insensitive filesystems
                - Fix 1/2 gridpoint shift in ARW nest locations in plots produced by plotgrids (thanks to Winston Hao)
                
                - Added support for NavySST GRIB data
              - Added Vtables for ARW output in GRIB format (thanks to Tanya Smirnova)