Just got back from Idaho, we usually go in Mid September and the weather is pretty mild. We spike camp in. This year we had one night when it got really cold, relatively speaking due to the smoke in the air. Brought up an issue I haven't had to deal with before. We woke up and all of our water and filters were frozen. Question is, when it is cold all the time, any suggestions on how you keep your water from freezing. I put my filter in my sleeping bag. That morning when our water bottles and camp water was frozen, we got by, but what if it was below 30 during the day and 20's at night. Do you just keep a short ration of water? We usually make 5 gallons to keep in camp to fill out bottles and hydration bags with in the morning and cooking so we don't have to make water everyday. Any help appreciated.