For your climate, a full size 10 frame deep brood box will need approximately 70 pounds of honey for the winter and they need pollen stored up for the spring. You might try feeling how much an empty hive with the frames, wax, tops and bottoms feels and compare that to your hive. My father-in-law lives in PA and that is his normal goal for his hives. I pick up the back of the hive to see if they have enough food. If you do it on a regular basis when you have been in the hive to see how much food they have, you will be better able to judge how much stores they have.
Jim