Great Plains Studies, Center for


Date of this Version

February 1991


Published in Great Plains Research 1:1 (February 1991), pp. 77–92. Copyright © 1991 The Center for Great Plains Studies, University of Nebraska–Lincoln. Used by permission.


This study identifies the spatial variability of the hydroclimatology of the Great Plains. Spatial associations of monthly midtropospheric circulation anomalies, total precipitation, and mean stream discharge are identified using an unrotated principal component analysis. Three hydroclimatic associations, representing synoptic circulation features and associated precipitation and stream discharge patterns, identify specific circulation anomalies and corresponding spatial pattems of surface hydrology in the northern, central, and southern Great Plains. Results indicate that nearly 47% of the hydrologic (precipitation and stream discharge) variability during summer is attributed to synoptic-scale midtropospheric circulation anomalies, with sub-synoptic convectional processes accounting for approximately 42% of the hydrologic variance.