Climatology of westerly wind events in the lee of the Sierra Nevada

In this study we present preliminary results for the climatology of westerly wind events in Owens Valley in the lee of the southern Sierra Nevada. This climatology is derived from the data recorded by the mesonet of sixteen automatic weather stations located in Owens Valley near Independence, which was installed by DRI in preparation for the Sierra Rotors Project in 2004. This long-term network, which has been collecting 30-second data since the end of February 2004 was also an integral part of the ground-based instrumentation suite in the recently completed Terrain-induced Rotor Experiment (T-REX) in spring 2006.

The preliminary results of this climatology, based on two years of data, indicate that the occurrence of strong westerly winds in the Sierra Nevada lee has a bimodal distribution with a primary peak in spring (Mar-Jun), and a secondary peak in late fall (Dec). Diurnal distribution of these events shows predominance of strong westerly wind events in the late afternoon hours.