The Pacific/North American Teleconnection Pattern and United States Climate. Part I: Regional Temperature and Precipitation Associations

Abstract

Abstract The Pacific/North American (PNA) teleconnection index, a measure of the strength and phase of the PNA teleconnection pattern, is related to the variations of the surface climate of the United States from 1947 through 1982 for the autumn, winter, and spring months when the PNA is a main mode of Northern Hemisphere midtropospheric variability. The results demonstrate that the PNA index is highly correlated with both regional temperature and precipitation. The strongest, most extensive correlations between the index and temperature are observed in winter, but large areas of the country show important associations during the spring and autumn as well. Although the centers of highest correlation migrate systematically with changes in the circumpolar vortex over the course of the annual cycle, the southeastern and northwestern parts of the United States possess consistently high index-temperature correlations. Correlations between the PNA index and precipitation are weaker and less extensive than those...