New winter travellers tend to fixate on the parka. Experienced ones think in systems — layers that trap and manage heat, and the discipline to adjust them before they’re wet or freezing. In the North, “staying warm” is really “staying dry and adjusting early.”
The layering system
Think in three jobs, not three garments:
- Base layer wicks sweat off your skin. Wool or synthetic — never cotton, which holds water against you and stops insulating. This is where a lot of cold injuries start.
- Insulation traps warm air. Down is warmest for its weight but useless wet; synthetic keeps working when damp. Carry enough that you can add a big puffy the moment you stop moving.
- Shell blocks wind and precipitation. Wet plus wind is how hypothermia begins even in summer up here, so a waterproof jacket and pants earn their place year-round.
Adjust before you have to
The single most useful habit in cold travel: vent early. If you’re sweating on the climb, you’re soaking the insulation that has to keep you alive at the top. Shed a layer or open a vent before you’re damp, and add the puffy the instant you stop. Cold-and-dry beats warm-and-wet every time.
The sleep system is half the battle
Most of your overnight heat loss goes into the snow beneath you, not the air. A warm bag on a cold pad is a cold night.
- Rate your bag for the coldest night you might see, not the average. In deep winter, that means a bag rated well below zero — a −40 bag for a −35 forecast.
- Insulate from the ground. Use a high R-value pad, and in deep cold stack a closed-cell foam pad underneath it as a backup and extra buffer.
- Sleep in dry layers. Change out of anything damp before you get in.
The small things that bite
- Extremities and spares. Insulated gloves plus liner gloves, a warm hat, a buff. Carry backups — a soaked pair of gloves at −30 is an emergency.
- Frozen water. Uninsulated bottles and hydration hoses freeze solid. Insulate them or carry them inside a layer, and plan fuel to melt snow.
- Glare. Sun on snow causes snow blindness fast. Eye protection isn’t optional on open terrain.
WayUpThere scales all of this to your actual trip — season, duration, and whether you’re above the tree line — and estimates the stove fuel you’ll burn melting snow. Because the warmest gear in the world doesn’t help if it’s the thing you left at home.