Simulations provide an important tool for understanding and predicting the atmospheric boundary layer, but we need to incorporate both realistic large-scale weather effects (mesoscale) as well as refined localized turbulent variability (microscale) with large-eddy simulations, transcending previous idealized approaches. We have investigated and tested new approaches for simulations across scales (Mazzaro et al. 2017 JAMES, Mazzaro et al. 2019 JAMES). We have demonstrated such coupling for a diurnal cycle in a wind farm, facilitated with cell perturbation methods (Muñoz-Esparza et al. 2017).