Layering in the Pacific Northwest:

Knowing how to layer clothing will determine whether you are comfortable or uncomfortable in winter conditions. But be aware that the information here is for winter conditions of the Pacific Northwest, which are comparatively mild—meaning conditions between 0–45º F on average in elevations between 1000–7000 ft and winds that are mostly 0–25 mph and rarely up to gale force. You will likely need more insulation in colder regions, which is why in many places people are traveling on skis pulling heavier gear on a pulk, rather than backpacking in snowshoes. In Pacific Northwest, it is not difficult to backpack in winter with a 25–35 lb backpack. The mountainous terrain here would make pulling a pulk nearly impossible. Nevertheless, some of the basic techniques described in this short introduction to layering may be useful in other destinations.

Winter layers need to serve four purposes

1. Preventing overheating and sweating
2. Preserving body heat
3. Protection from moisture (sweat, snowmelt, condensation, and rain)
4. Blocking wind

To achieve these goals, fast-wicking, insulated, and waterproof types of clothing are used in various layered combinations.

Two categories of layering

If you are a beginner, it helps to think of layering in two categories: 1) layering for hiking and 2) layering for camp. When hiking, the main objective is to stay warm without overheating and sweating too much. The moisture from sweat wicks the warmth away from your skin causing you to lose body heat. Once you reach camp and stop hiking, you are no longer generating as much heat and you need to insulate the body to prevent heat loss. The main objective is always to prevent loss of body heat. You want to avoid putting too many layers on while hiking and, likewise, it is best to avoid wearing your sweaty hiking clothes around camp.

Layering while hiking

People have different requirements. Generally speaking, what works for me is one or two synthetic top layers, consisting of a nylon t-shirt, and a UV pullover with a hoodie. If the weather is going below 25º F, I will wear a thin nylon base layer or thermals under my regular summer hiking pants (standard convertible pants). Many hikers prefer “soft-shell” pants used by climbers, but I find them to be too warm. I prefer a combination of regular hiking pants, a thin base layer, and rain pants if necessary like this:

• Regular hiking pants (temperatures above 25º F, on ascents with 25–35 lbs pack)
• Regular hiking pants with a thin thermal base layer (temperatures below 25º F, on ascents with 25–35 lbs pack)
• Regular hiking pants with a thin thermal base layer (temperatures around 40º F, flat terrain, no pack, casual speed)
• Regular hiking pants with rain pants (high winds or snowing)

If the weather is in the 5–10º F range, I may wear a nylon-wool blend pullover or a fleece pullover, and possibly a rain jacket if it is snowing or wet. If I am hiking uphill, typically gaining 3000–4500ft in elevation, I may only need one layer while hiking. When coming down I will burn less energy and need more layers. Heat is generated by movement, so what I’m doing, ascending or descending, is as important as the air temperature and wind chill. Either way, I subscribe to the one-jacket strategy. If I stop for any length of time, I quickly pull out a thick puffy down jacket to preserve my core warmth. In warmer and wetter conditions, I may take a synthetic puffy jacket instead of a down one. Synthetic jackets retain loft better than down when wet, and loft is essential to warmth.

When you are starting the hike at a trailhead, you usually want some extra layers such as a fleece or wool pullover or down jacket while you are getting ready and waiting on others. You can pull off this extra pullover or down jacket when you start to hike (the cold-start method) or usually 10–20 minutes into the hike when you begin to overheat. Commonly, the group will stop shortly after starting to take off a top layer. A common miscalculation is for a hiker to wear a base layer bottom when it is unnecessary. Getting a base layer bottom off when you are hiking in deep snow with snowshoes on is difficult and time-consuming. 

When there is strong wind, I wear rain pants and a rain jacket. Rain gear needs to be waterproof to hold out wind, so look for pants and jackets that have zipped vents that can allow in air if you begin to overheat and sweat. I use a balaclava and goggles to protect my face. I use a very thin lite-weight balaclava in the spring and summer for UV protection and a warmer insulated balaclava for late fall and winter. I carry multiple fleece liner gloves for hiking.

Layering at camp

Because your hiking clothing becomes sweaty while hiking, the recommended practice is to switch into a fresh base layer at camp. This base layer is for hanging around camp and sleeping at night. If it is cold and windy, the sooner you get into this fresh base layer the better. You then add down pants or rain pants for activities around camp, such as cooking and socializing. You also wear a puffy down jacket with a hoodie. If it is windy or snowing you may need to wear rain pants and a rain jacket over your down-insulated clothing to keep out moisture from melting snow.

The ability to keep your body protected from moisture, such as melting snow and the windchill is essential, which is why rain pants and a rain jacket are required. Ultra-lite windbreakers are not robust enough. You need moisture protection. If moisture and wind are threats while hiking, it helps to have full-zip rain pants that can be put on easily without having to remove snowshoes. Otherwise, lighter partial zip rain pants will do the job. 

I carry a pair of cold-weather waterproof gloves for handling snow, and a double-layer mitten system for windy conditions and keeping my hands warm while hanging out around camp in temperatures in the 5–15º F range. You want to have gear that gives you peace of mind, the knowledge that if a perfect storm of unfavorable conditions strike, you are going to be okay, if not comfortable.

Being comfortable in harsh beautiful conditions is the most sublime wilderness experience you can have.

I tend to avoid mid-weight layers. When I’m not burning energy, I have one well-insulated jacket that I put on. It is good for the harshest conditions I’m likely to encounter. But I’m not a climber, so I’m not looking for a bullet-proof 3 lb 30D expedition jacket, just something really warm with a good weight-to-warmth ratio (my parka is 20D, 800 fill, 1 lb 4 oz total). I do want to be comfortable, but the expedition-level gear isn’t really necessary for backpacking trips in the Cascades below 8,000 feet. That said, it is important to watch the forecast and know the limits of your gear. The coldest recorded temperature in Washington State was around –40º F, a freak event to be sure, but my gear will not keep me comfortable if the cold plunges that low.

Winter layering gear list

Use these lists to help remind yourself of essential gear when packing.

Hiking clothes

Typical hiking layers: 1) UV pullover shirt with hoodie (especially March–July), 2) Light nylon t-shirt, 3) synthetic underwear, 4) Convertible hiking pants, 5) light nylon thermal layer for temps in the 10–25º F range, 6) Liner socks (wool) plus thick boot socks (wool blend), 7) Gaiters (knee-high), 8) Belt, 9) Fleece liner gloves (100 g/m2), 10) light down jacket that is worn at the trailhead and usually removed shortly after the start of the hike, 11) Buff, and 12) Helmet (recommended when snowshoeing on steep slopes and anytime an ice ax is required)

Easily accessible layers in the backpack (packed in a dry sack):

• Down parka with hoodie (keep near top of the pack)
• Synthetic parka (alternative for warmer rainy trips)
• Fleece or wool pullover
• Rain pants
• Rain pants (full zip type—when high winds are expected) If you are using rain pants while hiking for rain protection, put rain pants on over your gaiters to keep water from flowing inside the gaiters and into your boots.
• Rain parka with hoodie (Robust and reliable, not merely a windbreaker. Keep near the top of the pack.)
• Insulated balaclava (mainly November–February)
• Goggles (mainly November–February)
• Gloves (waterproof)
• Inner mittens
• Outer mittens (for harsh conditions combined with inner mittens)
• Lite UV balaclava (mainly March–July)
• Glacier glasses (mainly March–July)
• UV nose shield (clips to eyeglasses)
• Cap (provides eye and UV protection) Most caps are cotton. You can find lite nylon caps by searching for running caps.

Less accessible layers in the backpack (packed in a dry sack):

Packed for all trips:

• Thin thermal base layer pants (nylon or Capilene base layer)
• Thermal base layer top (long sleeve)
• Liner socks (wool)
• Thick boot socks (wool blend)
• Beanie (wool)

Packed for some trips:

• Mid-weight thermal base layer pants (mainly January–March, if 0–15ºF weather) 
• Down insulated pants (optional, mainly January–March, if 0–15ºF weather)
• Down insulated booties (optional, mainly January–March, if 0–15ºF weather)
• Down insulated pants (optional, mainly January–March, if 0–15ºF weather)
• Vapor barrier socks (for around camp, especially March–July)

Gear weight

Generally speaking, much of the gear available for climbers, snowboarders, and skiers is made with materials heavier than what is required for winter backpacking. For backpacking, it is important to focus on the warmth-to-weight ratio.

Nine winter layering essentials to know

1. Don’t wear too many layers when you are hiking (you’ll overheat and get sweaty).
2. Put on layers quickly when you stop to rest or set up camp (don’t lose body heat).
3. Always sleep in a dedicated base layer.
4. Take off layers when you are too hot to avoid sweat.
5. Avoid getting wet from snow (wear gaiters and waterproof gloves).
6. Wear fast-wicking fabrics. Avoid cotton because it doesn’t have good wicking properties causing it to increase the risk of hypothermia.
7. Take wind protection seriously and be able to cover all flesh.
8. Take UV protection seriously and be able to cover all flesh (especially March–July on snowfields).
9. Protect your gear from moisture. Gear can easily get wet in unexpected ways (see Preventing Wet Clothing below)

Preventing wet clothing

Packing clothing in dry sacks or plastic bags is not enough. There are three main ways your gear can get wet:

1. In your backpack: Gear in your pack can get wet from snow on trees and limbs brushing against your pack, from setting the pack on the snow, from the sun melting snow in the treetops and dripping down on your pack while hiking in the forest on a clear day, and from snow converting to rain in lower elevations. Gear can also get wet from leaking pack bladders or water bottles. A leaking pack bladder is a much more serious problem in the winter than in the summer, so pack bladders are not recommended. It is best to store water bottles in the outside pockets of your pack clipped with mini-wire carabiners to help ensure they don’t fall out. Most of these threats can be neutralized by storing clothes and sleeping bags in dry sacks or plastic bags. (I usually pack camp clothes together with my sleeping bag in one compression sack.)
2. Body heat melting snow: This is especially likely in temperatures between 25º and 35º F (a common winter temperature range in the Cascade mountains). Setting up camp, digging a cooking pit, or building a snow wall are situations that can lead to wet clothing and especially gloves. Waterproof gloves are best for these activities. Vapor barrier socks are a good way to protect socks and down booties from moisture around camp.
3. Tent condensation: Pack clothing in your sleeping bag or in a tent sack that you can use as a pillow. Avoid leaving clothing outside your sleeping bag along the edges of the tent where condensation can run down the tent walls. Be aware that if it is 25º F outside, it can easily be 35º F inside your 4-season tent. This means condensation will not turn to frost inside the tent, but rather will become water collecting around the edges of the tent floor and on the surface of your sleeping bag. Sometimes it is best to leave the tent door open to keep the tent cool. I never include potential tent warmth in my calculations when selecting which temperature-rated sleeping bag to take.

Expect to gain experience gradually

People have different requirements. The only way to learn your own layering needs is by experience and that takes time. It helps to begin with short day hikes and snowshoe trips. For safety pack more than you may require and try to start by hiking with someone who has experience.

I never hike alone in winter and I don’t recommend solo winter hiking to anyone. It’s okay to snow camp alone, but traveling on snow alone is dangerous because you can fall through the snow into a tree well, deep hole, or stream, and your tracks can be blown away by the wind or covered over by new snowfall.

When you are camping overnight, you have the gear you need for multiple days. When day-hiking in the winter, be sure to pack enough gear so that you can protect yourself from cold without a fire if you have to stay out overnight. You should carry a fire starter, but you should not assume a fire will be possible or safe, especially in some parts of the Cascades. It may be impossible to light a fire in winter conditions in some areas of the mountains because the snow can be too deep and wet. If you try to collect wood when the ground and trees are covered in deep snow you will likely get wet while failing to build a fire increasing your chances of hypothermia, or you may fall into a tree well and die. For those reasons, don’t rely on warmth from fires. Always pack layers that will keep you warm and dry. Fires are inefficient and unnecessary when you have the right gear, which is why we have never built fires on any of our backpacking trips at any time of the year. Correct layering is the key to being warm, dry, and comfortable while winter backpacking.

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I will try to get some more illustrative photos for this post and update it later.

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What’s your experience? Have questions or insights, please leave your comments below.