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incorrect expression for "moist theta"

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have seen a couple of references in the WRF documentation to "moist theta", which I take to be the virtual potential temperature used in density calculations. Assuming that I'm attaching the right meaning to this variable, the expression cited is incorrect.

For example, in the output from ncdump -c, I find the following reference to the perturbation moist potential temperature:

pert moist pot temp=(1+Rv/Rd Qv)*(theta)-T0

The Qv multiplier Rv/Rd = 461.5/287 = 1.61 is incorrect; rather it should be (Rv/Rd-1) = 0.61.

Also, in the README file for namelist variables that accompanies the source code, I find

use_theta_m = 1 ; 1: use theta_m=theta(1+1.61Qv)
0: use dry theta in dynamics

Once again, the stated multiplier for Qv is incorrect. I don't know whether this incorrect expression is also used in the actual computations in the WRF source code, but if it is, it should be corrected, as it would seriously overestimate the effect of humidity on density.

By the way, there is an "issues" page on a github repositoryfor WRFv3 that is apparently not being monitored:
Thanks for the reminder about the NCAR github page not being monitored. We are in the process of cleaning that up. Our official page for the WRF modeling system will be (and WPS). On the old site,, we are probably going to only have a pointer to our official page.