Response of the wind system in Owens Valley to synoptic and mesoscale forcings—T-REX observations vs. model

This study analyzes the air flow over the Sierra Nevada (California) during a three day period and illustrates the response of the wind system in the 3 km deep Owens Valley to changing synoptic and mesoscale influences. Beginning with a relatively quiescent phase a nocturnal regime was replaced by a very strong channelling regime on day one, weakening but prevailing throughout the next night. On day two the channeling regime was weaker and observations indicated emerging mountain waves at crest level. Finally, a strong downslope windstorm evolved on day three. The passage of a cold front ended the downslope windstorm regime . The comprehensive observational data set of the Terrain-induced Rotor Experiment (T-REX), consisting of ground based measurements (automatic weather stations, instrumented towers and a car), remote sensing (lidar, sodar, wind profiler), radiosondes and dropsondes and airborne measurements, was analyzed and compared to high resolution numerical model runs conducted with the Weather Research and Forecasting (WRF) model.