Version 3.1 of the WRF Pre-Processing System (WPS) was released on April 9, 2009.

WPS Version 3.1

New features and bug fixes

• Added support for MODIS-based land use categories as an alternative to USGS categories
• Process static fields for the gravity wave drag schemes in both the ARW and the NMM
• Generalized treatment of 3-d soil moisture and temperature arrays
• Land use data sets with multiple water categories can now be handled
• Added support for sigma-level GRIB1 data
• Various fixes to interpolation schemes (thanks to Hyeyum Shin and Jeremy Krieger)
• The calc_ecmwf_p utility now creates a 3-d geopotential height field to give a correct vertical interpolation in real.exe (thanks to Daniel van Dijke, Chiel van Heerwaarden, and Ravan Ahmadov)
• The plotgrids utility can now handle NMM nests (thanks to John Halley-Gotway)
• Fixed a problem with using 30' data and lat/lon grid.