We present observational evidence demonstrating dynamic interactions and feedbacks between multi-seasonal snow cover and winter-time circulation anomalies over mid-high latitudes. The cooling effect of snow cover is associated with a strengthened and more expansive Siberian high with more frequent, topographically constrained intrusions west and north. Early-season snow cover variability leads to altered general circulation patterns consistent with the dominant mode of winter variability observed in the Northern Hemisphere troposphere. The implications of the surface-atmosphere coupling for seasonal to interannual predictability are also discussed. ¿ 1999 American Geophysical Union