SREF - Vertical Velocity Problem

Update 2013-07-25: The vertical velocity problem in the SREF WRF-NMM and NMM-B members has been resolved as of the 09Z cycle on 2013-07-25. Images dependant on vertical velocity have been restored to the webpage.

Update 2012-12-21: The calculation of the depth of the dendritic growth zone has been updated to remove any dependence on vertical velocity. Updated graphics for the following are available beginning with the 2012-12-20/21Z run of the SREF:


The new dendritic zone calculation is considered to be experimental and may not be available for every SREF run.

Previous update:

The WRF-NMM members are using a hydrostatic version of the model, which does not output vertical velocity. Meanwhile, the magnitude of the vertical velocities in the NMMB members are much too low.

A fix to the vertical velocity fields is unlikely until the transition to the new NCEP supercomputer (i.e., WCOSS) occurs at the end of the summer of 2013. On the WCOSS, a version of the NMMB with a vertical velocity fix has already been installed and increased computing resources should allow for the usage of a non-hydrostatic version of the WRF-NMM.

Graphics removed:

  • [PR]:700mb_Omega_<=-3
  • [PR]:700mb_Omega_<=-6
  • [PR]:700mb_Omega_<=-9
  • [MN]:Precipitation_Type_(SPC_Czys_Algorithm)

Graphics modified: (removed UVV reference and UVV field)

  • [MN]:700-500_UVV~3hr_mean_QPF
  • [MD]:700-500_UVV~3hr_median_QPF
  • [PM]:700-500_UVV~3hr_prob_match_QPF