So, by tone I'm assuming you mean an increase in muscle size and decrease in bodyfat percentage? Can you give us some numbers of where you want to be? ie. gain 15 lbs and reduce bodyfat percentage from 14% to 9%. I'm making numbers up, but you get the idea.
Your best bet would be to gain muscle and fat until you are as strong/ big as you want to be and then lose the fat. You also should look at your diet, probably add alot more protein and lose the processed carbs and fats.
Also, I live in Maryland, and the snow isn't that bad. You might be able to find a gym nearby. You're gonna have a hard time working legs with only bodyweight exercises.