Frostfall is a survival mod that adds cold weather survival gameplay elements to The Elder Scrolls V: Skyrim.
The three main components of Frostfall are Hypothermia, Cold Water Survival, and Camping Equipment.
The primary objective of this mod is to add a deep, immersive level of gameplay to Skyrim, while keeping tedium to a minimum. An immersion mod should never get in the way of having fun.
Frostfall uses a sophisticated system to track your location, weather, time of day, worn clothing, and more, to determine your current condition, in a seamless and immersive way. It also features a large variety of craftable camping equipment, including craftable torches, backpacks, and cloaks. It is highly customizable, and very compatible with most other mods, including Climates of Tamriel, cloaks, camping, food, timescale, lighting, werewolf, and vampire mods, and all official DLC.
If you want a very quick, dirty version of what this mod is, what it does, and how to start it, see the FAQ page.