The WRF model tar file has been updated to Version 3.3.1 on September 22, 2011.

The WRF Pre-Processing System (WPS) has also been upgraded to Version 3.3.1.

WRF Version 3.3.1 improvements and bug fixes

WRF-NMM specific updates

• Fixed uninitialized variables

HWRF specific updates

• SAS scheme (namelist option 84): fixed an out-of-bounds bug. Impacts: This bug caused the code to crash on Linux with PGI compiler. It also cause the model outputs to be different on different platforms (such as IBM and Linux/Intel)
• The CO2 transmission coefficient table now is calculated at runtime, instead of using a hardwired input.

General updates

Phyiscs:

• Microphysics:
• Thompson microphysics: modified fall speed; changed graupel size distribution (small effect); fixed processor-count-dependent results (thanks to A. Lenzen)
• WDM5, WDM6: fixed missing density term in auto conversion from cloud to rain, resulted in reduction of cloud water mixing ration (thanks to M. Gilmore)
• SBU scheme: unit correction (small effect)
• Morrison scheme: fixed a number of issues (see detail in phys/module_mp_morrison.F
• replaced kinematic with dynamic viscosity
• replaced scaling by air density for cloud droplet sedimentation with viscosity-dependent Stokes expression
• use Ikawa and Saito (1991) air-density scaling for cloud ice
• corrected typo in 2nd digit of ventilation constant F2R
• unit correction to use Kelvin (not Celsius) for temperature for accelerated melting due to collision of snow and grupel with rain (reported by K. Van Weverburg)
• fix to not subtract NPRACS from snow number concentration since decrease in snow number is already accounted for by NSMLTS
• fix in switch for running w/o graupel/hail (cloud ice and snow only)
• Cumulus:
• GD/G3 cumulus: fix for cloud water conservation (will result in reduction of surface rainfall)
• GD cumulus: fix to prevent possible division by zero (no effect on results (thanks to E. Kemp)
• NSAS cumulus: fix for cloud water and cloud ice tendency output for Ferrier and Kessler schemes
• Planetary Boundary Layer:
• YSU: minor change to allow the scheme to work with thin surface layer
• ACM2: increased dimension for message
• Surface Physics:
• PX LSM: change to prevent use of landuse categories other than 24 cat USGS (modis support to come in next release)
• RUC LSM: fixed uninitialized variable (reported by C. Chen); important correction to 2m T diagnstic when RUC LSM is used with MM5 surface layer option
• sst_update: fixed a problem with two-way nesting when sst field itself is masked
• Ocean mixed layer: added condition for tml < tmoml, then tml=tmoml
• Wind-farm (drag): fixed a bug to find wind turbine location (thanks to Y. Ma)

I/O:

• grib1: fix to remove uninitialized variable (reported by C. Chen)
• Add diagnostics for max/min, time of max/min, mean and standard deviation values of surface variables: T2, Q2, U10, V10, skin temperature, time-step rainc (raincv and rainncv). The option is controled by namelist output_diagnostics = 1, and output goes to auxiliary output stream 3 by default (thanks to L. Fita, J. Fernández, and M. García-Díez of Spain)

Software:

• ESMF updated to 5.2.0r
• p-netCDF support for io quilting: modified to reduce the size of storage needed. This helps to reduce the wrf executable size on some IBMs by a factor of 10 (thanks to A. Porter of UK).
• bug fix for configuring on a ubuntu or openSUSE system
• fix for serial build with nesting (revealed by gfortran)