RECOMMENDED GEAR-OUTER LAYER
HOODED BUBBLE COAT
A well insulated, wind and rain resistant coat with a hood is the only recommendation here.
These are to wear on top of your thermals and under your snow pants if you want the versatility of taking on and off your outer pants. They can also act as another layer of wind break.
A good neoprene face mask is vital in heavy winds that would otherwise leave your face frostbit.
The Bat is my own invention and I am very happy with it so far. You start with a pair of break-away athletic pants, sew seams across them horizontally and then make small slits in the mesh behind and below each seam. Pieces of cut up emergency blanket can then be stuffed through the slits and into the sections created by the seam. What you end up with is a layer of mesh, a layer of crumpled up emergency blanket, and a layer of windbreak. See below.