

This equation was used when calculating the power output shown in Fig. 12 in Fitch et al. (2012). The code distributed with the Weather Research and Forecasting Model (WRF) (versions 3.3 and onward) is unaffected.
REFERENCE
Fitch, A. C., J. B. Olson, J. K. Lundquist, J. Dudhia, A. K. Gupta, J. Michalakes, and I. Barstad, 2012: Local and mesoscale impacts of wind farms as parameterized in a mesoscale NWP model. Mon. Wea. Rev., 140, 3017–3038.