As of version 3.7, WRFDA has an improved radar data assimilation capability: there are now two different options for assimilating radar reflectivity data. The first (use_radar_rf) directly assimilates the observed reflectivity using a reflectivity operator to convert the model rainwater mixing ratio into reflectivity and the total mixing ratio as the control variable, as described in Xiao et al., 2007 (http://journals.ametsoc.org/doi/full/10.1175/JAM2439.1); this is the only option available in previous versions of WRFDA. For this option, the hydrometeor partition using a warm rain scheme described in the above reference can be turned on (use_3dvar_phy = .true.). The second (use_radar_rhv) is a scheme described in Wang et al, 2013 (http://journals.ametsoc.org/doi/full/10.1175/JAMC-D-12-0120.1), which assimilates rainwater mixing ratio that is estimated from radar reflectivity, described as an “indirect method” in the paper. This second option also includes an option (use_radar_rqv) that allows the assimilation of in-cloud humidity estimated from reflectivity using a method described in Wang et al, 2013. It also includes the assimilation of snow and graupel converted from reflectivity using formulas as described in Gao and Stensrud, 2012 (http://journals.ametsoc.org/doi/abs/10.1175/JAS-D-11-0162.1).