Layering for Winter Operations

Preparing for a search and rescue mission takes careful planning, especially when you're dealing with below-freezing temperatures. At our winter operations training weekend, we help CAP ground team members prepare both physically and mentally for cold weather conditions.

The first step toward preparing is being well dressed. Dressing for extended durations in the cold looks far different than just throwing on a thick coat, the way you might if you're waiting for the bus or clearing your driveway.

Instead, you'll want a more strategic approach of wearing layers.

These layers should be things you can take off and put on without too much difficulty.

After all, when you’re moving in a search line through the woods or carrying a stokes basket, you might find yourself getting warm. But when you’re doing something less intense, like taking notes or on a rest period, you're sure to get cold again.

Here are best practices for each layer:

Base Layer

The layer closest to your body is called your base layer. It keeps you dry if you sweat or if melting snow or rain gets through your other layers. This layer should be made of moisture-wicking material that fits close to your body comfortably. If it's too tight it will be uncomfortable and restrict your movement, and if it's too loose, it'll bunch up, causing chafing and moisture collecting in the folds.

Common materials for this are polypropylene, polyester, and wool.

• Synthetic materials are hydrophobic and repel water, which helps you stay dry. They’re lighter than wool, take up less space, and are generally less expensive.

  
  

• Wool isn’t hydrophobic, but the natural fibers still wick water away to keep you dry. Another advantage of wool is that it retains about 80% of its insulative properties even when wet. It tends to hold less odor than synthetic materials. It often gets a bad rap for being itchy, but unlike traditional wool, merino wool and alpaca wool are soft and comfortable.

  
  

• While you can generally find base layers in cotton at low prices, we don't recommend cotton. It doesn't wick moisture as well, takes a long time to dry, stays cold when it gets wet, and doesn't insulate as well as synthetics or wool. Unless you want to risk being cold, wet, and miserable, do yourself a favor and invest in something that will keep you dry!

Example of synthetic base layers worn by staff training candidates. A base layer is a great idea not only for winter, but also for spring and fall where the temperature rises and falls significantly within hours. They keep you warm in the mornings without being stifling later in the day.

Insulation Layer

The next layer is your mid-layer, or insulation layer. This layer traps warm air close to your body. It includes your normal uniform as well as any other layers you choose to wear, like a jacket liner or a fleece.

Rather than one thick coat, it’s better to wear multiple thinner layers to make up your insulation so you can add or remove layers as needed throughout the day.

(Pro tip: When you pack your gear, make sure you leave enough room in your daypack so you can stow away layers you remove.)

You don’t want the insulation layer to be skintight. Remember, this layer works because it traps warm air close to your body, so you need to leave room for those pockets of air!

A fleece is a great option for this layer, with the added bonus that the material is somewhat water resistant. It won’t hold up to a pouring rain, but it will help against a drizzle or snow.

A fleece, whether ABU style or the Hawk Mountain fleeces available at the base exchange, is a great insulation layer that traps warm air in without restricting movement.

Shell

The outside layer is your shell, or windbreaker layer. Wind makes you cold because it blows through the fabric in your layers and replaces the warm air close to your body. An outer shell will block most or all of that wind, allowing you to stay warmer. This shell also protects you from rain or snow.

Gore-Tex is a popular brand and is what the ABU parkas are made of, but there are a number of other options to investigate, each with their own pros and cons. The key things to look for are the qualities of being resistant to water and wind.

You can add or remove a jacket liner to your outer shell for extra insulation.

(Pro tip: Keep in mind that if it’s sufficiently cold, you may want to hold your water inside this outer shell to keep it from freezing. Internal pockets are very helpful!)

An effective shell/windbreaker layer is resistant to both rain and moisture. The parkas like this cadet is wearing will protect the wearer from losing heat to the wind, and keep the wearer dry even if they get covered in rain or snow.

Additional required clothing items

Hat

People often say that you lose 70% of your body heat through your head. This is based on an old study that didn't hold water over time.... but even though that it isn’t the case, you still lose heat proportionally to the rest of your body. It makes sense to wear a hat and hold that heat in. A knit hat will keep your head warm, and it’s especially important for your ears since they’re susceptible to frostbite.

Just like other layers, you should add or remove your hat as needed throughout the day. Some people in this picture chose to take off their hats due to warming up while hiking.

Gloves

With your fingers susceptible to numbness and frostbite, gloves are crucial.

Gloves can come in many forms, with advantages and disadvantages to each. Some are more waterproof and insulated but bulkier, while others are thinner and allow more manual dexterity, but aren’t as warm.

Consider getting one thick pair you'll wear most of the time and one thinner pair of gloves that you’ll wear when you need to do more precise things, like use your compass or take notes.

Winter gloves do NOT replace your leather gloves; you will need both.

Insulated boots

Insulated boots are an important means of keeping snow out and warmth in. And since you go hours on end without removing your boots, it's important to get a pair that fits you well, is broken in, and is warm enough for the conditions.

We reserve the right to turn away participants if they show up to our winter training without adequate footwear.

A small layer of insulation can go a long way toward keeping your feet warm and dry!

Socks

Insulated boots are fantastic, but one disadvantage is that they will trap moisture inside. Your feet are also susceptible to frostbite, making good socks crucial.

A good option is wool socks with synthetic liners. The liners wick away sweat, and while the moisture will be at least partially trapped inside the boot, the wool socks will stay warm even when wet. Always pack more socks than you think you need, because if your boots get wet on the inside, you’ll have to change your socks frequently to stay warm and dry. We recommend a minimum of six pairs of socks for a weekend training activity.

Insulated boots allow for an extra layer of insulation and water resistance for your feet. This is important if temperatures are below freezing, since your feet are susceptible to frostbite. Keeping your feet in working order is crucial to performing your assigned duties on any mission.

Socks and liners should fit well without getting bunched up, as that can trap moisture and/or lead to blisters.

Example of a wool sock and liner combo. These can be purchased as a pair (click image for link) or separately. Note: link does not constitute endorsement.

Optional clothing items

Besides the items listed above, also consider a scarf, mask, or neck garter to keep your face warm when the temperature plunges well below freezing, especially if the wind is blowing snow in your face.

Ear protectors can be used in addition to a hat, if desired.

Also consider gators, which keep the snow out of your boots.

Gators bridge the gap between boots and pants, keeping snow out of your boots. They're especially useful when dealing with deep, powdery snow.

One more thing to consider is taking some hand warmers. These shouldn’t be placed directly against the skin, but keeping them inside a pocket can add a lot of warmth. Be sure to read the manufacturers’ instructions for safety tips.

Example of a commercially-available hand warmer.

Cold weather can be intimidating, but with the right approach, you can learn to conserve your body heat and thrive even in difficult conditions. So choose your materials wisely, layer up, and we’ll see you on the Mountain!