Good protection breed for cold weather?

I may be moving to Ohio soon, and I'm planning to get a 2nd dog shortly after I arrive. I currenly own a 4.5 month old male Akita, and will be getting a female pup once he is about 7-8 months old. I support rescue, and will look for my next dog on Petfinder, but would like some opinions on a good breed. I prefer guardian breeds (hence the Akita) that are 70-100 lbs. as adults. Will need a double coat to endure the cold on walks and such (although it will be an indoor dog). I've researched many of the mastiff-type breeds, but am unsure how they do in the cold. Also considering a Malamute, German Shepherd, or Great Pyrenees. I know the males of these breeds can get over 100 lbs, but I'm looking for a female and so they may still fit into the size range I'm thinking of. The dog would live on 1-2 acres with a fenced yard and my Akita as a companion. Thanks for your opinions!