I am documenting the steps necessary to output ZNT, RMOL, and LANDUSEF (hoping to save other users the time it took me figure this out). There is no need to modify the registry in WRF Version 3.3
Step 1) Create a file to put in your run directory and call it "iofield_list.txt". Include the following line of code in the file:
+:h:0:ZNT,RMOL,LANDUSEF
The line above says add ('+') to the history file ('h') stream 0 ('0'; the standard stream) the time-varying roughness length, 1 over the monin-ob. roughness length, and the landuse fraction by category.
Step 2) Then add an entry to the namelist.input under the '&time_control' section. Make sure that if you have a nested domain you include a filename for each domain nest:
iofields_filename = "iofield_list.txt","iofield_list.txt"
That's it--you're ready to run the model and your new variables should be visible in the wrfout files.