If you are going to drive in the snow regularly, then get dedicated snow tires. Pick up a set of rims, either steel or alloys, here from a member selling them and have snows mounted and change them seasonally. That's what I do, but I travel upstate NY, NE and NW Pa a lot. 4 years ago I bought a set of XT rims and mounted Winterforce tires on them. I can tell you they are pretty unstoppable even in this recent blizzard, even before the roads were unplowed. But noisy on dry interstate roads.
But if this is FLUKE, and most of your winter is on dry, plowed roads, stick with an All Season tire, no need for a 2nd set or rims and someplace to store them. Just wait an extra few hours or day for the snow plow. Your Subaru will get you further than a normal vehicle, but will be hampered by tire traction under worse conditions.
98S, 2014 Impreza 5 dr Ltd (9 Subaru's since 1978, 7 were 5 sp) ILuvSubaru's