Figure i. Conceptual model for how fall snow cover/tropospheric precursors modify winter circulation in both the stratosphere and the troposphere; case for extensive snow cover/active blocking illustrated: 1. Snow cover increases rapidly in the fall across Siberia, when snow cover is above normal diabatic cooling helps 2. to strengthen the Siberian high and leads to below normal temperatures. 3. Snow forced diabatic cooling in proximity to high topography of Asia increases upward flux of energy in the troposphere, which is absorbed in the stratosphere.  4. Strong convergence of WAF indicates higher geopotential heights, a weakened polar vortex and warmer temperatures in the stratosphere. 5.  Anomalous geopotential heights and winds appear to propagate down from the stratosphere into the troposphere all the way to the surface.  6. Dynamic pathway culminates with strong negative phase of the Arctic Oscillation at the surface.
http://web.mit.edu/jlcohen/www/papers/Cohenetal2007.pdf