Dress in layers

Summary

This pattern is for walkers, hikers, cyclists and anyone spending a day outside in changeable conditions. It describes a three-layer clothing system and the habit of adjusting it early, so you stay dry and comfortable instead of soaked or shivering.

Recommendation	Why?
Wear a base layer of merino wool or synthetic fabric, not cotton.	Wicking fabrics move sweat away from your skin and stay warm when damp, while wet cotton holds water and draws heat out of your body.
Add an insulating mid layer, such as a fleece or light puffy jacket.	It traps warm air, and you can take it on and off quickly as conditions change.
Carry a waterproof, windproof shell, even if the forecast looks fine.	Wind and rain strip heat fast, and a shell weighs little compared with the trouble it saves.
Start a little cool.	You’ll warm up within 10 to 15 minutes of moving, and starting in everything means sweating into your clothes early.
Take a layer off before you sweat, and put one on before you get cold.	It’s much easier to stay dry and warm than to get dry and warm again.
Pack a hat and gloves.	You lose a lot of comfort through your head and hands, and they’re the smallest, lightest way to add warmth.
Carry one spare warm layer in a dry bag.	If you’re delayed, injured or get wet, a dry layer can make the difference between uncomfortable and dangerous.

Context

This pattern suits day walks, bike rides, school sports days, outdoor work and travel to places with cool mornings and warm afternoons.

It does not suit short trips where shelter is always close, or serious alpine and winter conditions, which need specialist clothing and training beyond this pattern.

There’s a trade-off between weight and margin. Every extra layer is something to carry, but the spare warm layer is what you’ll want if things go wrong. This pattern chooses a modest safety margin. On a short, well-known route in settled weather you might leave the spare at home; in remote areas or the mountains, carry more.

Usage

Before you go: check the forecast for the highest and most exposed point of your route, not just where you start, and lay out the three layers plus hat, gloves and spare. A reusable list helps, see Pack from a reusable list.

At the start: dress so you’re slightly cool standing still. If you’re about to do something strenuous, a short warm-up gets you to temperature without overdressing.

On the move: stop briefly to adjust at the first sign of sweat or chill, rather than pushing on to the next rest. Put your mid layer back on as soon as you stop for a break, before you start to feel cold.

When things change: if the weather turns or you’re running late, add layers early and think about heading back, see Set a turnaround time. Make sure someone knows your route by leaving a trip plan.

References

Your national or state parks authority and bushwalking or mountaineering clubs publish clothing and safety advice for local conditions. The care label and manufacturer’s instructions tell you how to wash and reproof waterproof shells.