While some canister stoves are lighter than liquid-fuel stoves, the latter work better in cold weather, since you can maintain the pressure in the bottle by pumping it. It’s also easier to gauge your remaining fuel by feeling the weight. For tips on buying, using, and fixing liquid-fuel stoves, see backpacker.com/liquidfuel.
On overnighters, you’ll need to melt snow for water. Budget about three times more fuel for winter trips than for summer ones. A good working estimate is 6.5 to 8.5 ounces of fuel per person per day (depending on the temp, stove efficiency, and how much spare fuel you want).
In the cold, your body needs extra calories to keep warm, so allocate as much as 4,000 to 5,000 calories per day. Pack dense foods like cheese, peanut butter, chocolate, pasta, and butter. And beware the freeze factor: Some energy bars and snacks, like almonds, turn bullet-hard in chilly temps, so opt for less-processed, whole-grain bars, such as Odwalla and Nutri-Grain, and dried-fruit snacks (cranberries, raisins, mango), which tend to stay soft even when the mercury plummets.