Intensity of Thunderstorm-Generated Turbulence Revealed by Large-Eddy Simulation

Thunderstorms are characterized by turbulent processes that constitute an important aviation hazard. Turbulence occurs within cloud and in the surrounding clear air but, despite its importance, the characteristics of thunderstorm-generated turbulence and its spatial distribution are poorly understood, especially outside of cloud. Here we use large-eddy simulation to characterize turbulence generated by a canonical thunderstorm. The simulation identifies regions of notable three-dimensional anisotropic turbulence more than 5 km above the storm, in a shallow layer above the storm's anvil, and a horizontally asymmetric pattern of weaker turbulence that extends more than 50 km horizontally away from the cloud. Our results provide the first continuous estimate of turbulence intensity in and around thunderstorms and represent a major step towards improved turbulence avoidance methods. The results also have broader implications for understanding fundamental aspects of how thunderstorms are maintained and affect their surrounding environment.