Abstract
Monthly accumulations of area-averaged precipitation along the West Coast of the United States are related to estimates of local circulation parameters. The annual cycle as well as anomalous components of these quantities are compared. A strong annual cycle in most of the circulation parameters reflects the influence of the large-scale circulation on the annual variation of the precipitation field. For the anomalous monthly components, especially in winter, high correlations are found between precipitation and sea-level pressure or 70 kPa height. Other circulation parameters are also significantly correlated with the precipitation. These include the zonal and meridional wind components and the advection of relative vorticity.
