Given the relatively wide spacing between turbines in the region – most of the turbines are located 10-20 rotor diameters (D) from each other in the direction of most frequent flow – this region presents an ideal test of the mesoscale WFP. Therefore, we identify numerous cases with wind speeds varying from 8-12 m s-1 in unstable and stable conditions. When flow is from the east, downwind wind speed and direction profiles from instrumentation located at Wasco, OR, can be used to quantify far-downwind wake behavior and assess the performance of the WFP. When winds are from the west, as is most common, the power measurements from the individual turbines are compared to those predicted by the WFP to assess the performance of WFP. Scanning lidar measurements from the Arlington field site document individual wakes from turbines in both easterly and westerly flow conditions.
Beyond documenting the benefits of forecasting with the WFP as opposed to simulations with no accounting for the effects of turbines on the flow, we test a number of improvements to the WFP that have been motivated from other studies in both real and idealized scenarios. These improvements include reductions in the amount of turbulence generated by turbines in the simulations and incorporating a stability-dependent turbulence generation in the WFP as suggested by recent large-eddy simulations. While our simulations use 1-km horizontal resolution, we also test the value of high vertical resolution with the WFP, including nominally 10-m and 20-m resolution in the lowest 200 m of the domain.