Many people have designed portable survival kits however there is a much higher probability of being stuck in the cold or the rain than needing many of the items in a typical survival kit. This is why I always carry my cold weather clothing kit.

The advantage of this kit is that it is light, easy to pack and augments the clothes that you are already typically wearing. When people are concerned about being cold, they typically carry an extra jacket but that takes up lots of space and only helps your upper body. My system warms you up by addressing the major ways that you lose body heat in the most effective manner. The hat covers your head which is often exposed, the shell blocks wind / rain and traps heat while the long underwear adds extra insulation under the pants that you are already wearing.

Most outdoor experts recommend a three layer system consisting of a wicking layer next to your skin, an insulating layer and an outer shell. Try to avoid cotton. This kit provides the outside layer for the top and the wicking layer for your pants as well as the addition of a hat.

Supplies

What is included:

Light weight rain coat
Warm hat
Long underwear bottoms
Small bag - Optional

Step 1: The Jacket

Shell jackets are great because they not only protect you from the rain but trap heat next to your body. This is especially important in windy conditions where the wind might blow through a fleece or sweater. With a shell and insulating layer you have a lot of versatility depending on the conditions.

When I travel, I usually bring a medium weight plain wool sweater. This keeps you warm on the plane and allows you to get into most restaurants at night as well as the opera. A wool sweater combined with an outer shell provides a tremendous amount of warmth and breathability. Of course, any other insulating layer such as fleece will work as well but the wool sweater is warm and can be formal if needed.

Pick a thin light weight jacket with hood. The purpose is to block the wind and rain. Do not get anything with insulation since it must fold up small and the insulation adds extra weight. You can use a simple rain shell or use Gore-Tex for more breath-ability. Under arm zippers are good for ventilation if you are hiking or doing other activities but they are not necessary. If you keep looking you can usually find a Gore-Tex jacket on sale or at stores like TJ Max or Ross.

Step 2: The Hat

If your feet are cold, put on a hat. While it is a myth that 40% of your heat is lost through your head, wearing a hat is still important since your head makes up 7% of the total surface area of your body. When you add the hood over your shell, you get additional warmth because it blocks the wind and you trap the air next to your head.

When traveling or hiking, hats are easy to take on or off for quick temperature regulation.

Any simple fleece hat will work and you can get them at the end of a season for 50% off or more.

Step 3: The Long Underwear Bottoms

When most people dress for the cold, they focus on the top layers but forget the bottom. By adding a pair of light weight long johns you can quickly add warmth to your legs under the clothes that you are already wearing.

When I travel, I usually bring a good looking pair of nylon pants or similar (no jeans or cargo pockets etc...). The combination of outer nylon pants and inner long johns is light weight, breaths well, warm, handles some rain and drys quickly. If you are wearing shorts while hiking you can still wear the long johns underneath if you don't have any other pants.

You can use any pair of simple long johns and can get them at Target or Costco for ~ $10. Just make sure they are nylon or polyester - no cotton. For most conditions, just use the lightweight wicking version or step it up to a slightly heavier weight if you get cold easily or going to a much colder location.

Step 4: Packing

I pack the hat, jacket and bottoms in a small packing cube with bright colors (so I can find it in my bag). This way I can throw it in the bottom of the bag and it is there when I need it. In a pinch, you can skip the packing cube and pack the jacket and the bottoms into the hat and tie it up with a string.

Step 5: Additions

While this system is designed to give the maximum warmth with the minimum weight and size, their are additional changes you can make to extend the system.

Glove liners - these thin gloves pack small and are great when you hands are cold and you don't have real gloves.
Lighter for emergency fire - if you get stuck outdoors, a fire creates light and heat and can also help people find you. Just make sure you take it out before getting on a plane.
Wool socks - Wool keeps you warm when wet and is a great when you are walking around in wet shoes. I usually wear wool socks when traveling because they don;t stink. Having a pair in your kit ensure that you are always ready. The thin ones take up less space and are sure to fit under most of your shoes. Remember, the key to warm feet is wool socks and a hat.

With a hat, shell jacket and long underwear bottoms, you can take the clothes that you normally wear and be prepared for much more severe conditions.