Cold Weather Considerations – Part 1, by JM

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(Note: This Part 1 of a six-part series.)

If you live in the northern hemisphere then it’s that time of the year when things are getting cold and, depending on how far north you live, covered in white stuff. Around Thanksgiving I start planning my various winter outdoor activities such as hiking, camping, skiing and snowshoeing trips, and I thought it would be a good time to review some considerations for surviving and operating in winter conditions. Why would anyone want to be outside in the cold and snow? Because in a post-disaster scenario you may not have a choice, and being able to operate effectively outdoors in a winter environment can potentially provide you with a significant advantage since most people will probably be doing everything they can to avoid it. I know that a lot of you hunt in late fall/winter time, so I encourage you to share any tips or experiences you may have in the comments.

I link to a number of different products in this article – a lot of these are things that I own, have used, or have had significant interactions with people that have used them. I find they work well for me and my requirements, but you should do some research and figure out what would work best for you. You should also note that as with any outdoor activity, being outside in cold and snowy conditions can result in bodily harm and injury, so make sure you’re prepared and properly equipped, let someone know where you’re going and when you’ll be back, and always have some way to call for help in case of an emergency. If you’re new to outdoor winter activities do some research, take some training or participate with someone that has experience.

Since this is a long article that’ll be broken up into several installments I want to provide an overview of what I’ll be covering:

  • Health
  • Medical Treatment
  • Clothing
  • Shelter
  • Sleeping
  • Fire
  • Food
  • Water
  • Movement
  • Firearms
  • Electronics
  • Operational Considerations
What is ‘Winter’?

The beginning of winter is usually considered to be the shortest day of the year, but I consider it to be any extended period of time where the temperature will consistently stay below 60°F. Why 60°F? – because you can be subject to hypothermia in wet or windy conditions below 60°F, so you need to be prepared to handle those colder environments. Real winter also tends to bring a lot of interesting and exciting weather conditions such as extreme cold, snow, blizzards, freezing rain, ice, ice fog, temperature inversions, whiteouts, low humidity and wind chill effects, any and all of which can have significant impacts on your body and your operational activities in the outdoors. Generally it’s a good idea to avoid going outside in conditions that can kill you, but in a post-disaster world you may be forced to in some circumstances so you need to be prepared. I know that doing things like camping and hiking in winter conditions might seem somewhat frivolous and a little crazy, but I’d rather learn what works and how to do things right while I have safe fallback options rather than when I’m forced to.

Winter and Your Body

Given that you are arguably your single most critical prep, you need to understand how winter can impact your body. Your body produces heat mainly through metabolic processes in your cells as it breaks down food and converts it into energy. Glucose (sugar) from food reacts with the oxygen you breathe to produce carbon dioxide, water, and energy. Some of this energy is stored to be used later, and some of it is released as heat. This is referred to as cellular respiration and it is the main way your body generates heat.

Under normal conditions your body regulates the amount of heat produced to keep a stable core body temperature of around 98.6°F. While pretty much any cell in your body can produce heat, some muscles and organs produce more heat during certain activities, so your body moves heat around to where it’s needed using your blood. Hence, two of the most important considerations for staying warm are ensuring your body has enough fuel to produce heat, and the ability to move it around via your blood.

We’ll talk about food later on, but the movement of blood to warm you up brings up the first important consideration – chemicals like caffeine, nicotine and alcohol (in larger quantities) are vasoconstrictors, which mean they cause the capillaries that move your blood around to contract, reducing the flow of blood. The effect can last up to several hours, so this means that you should avoid things like coffee (except for decaffeinated), cigarettes, chewing tobacco, nicotine gum, vaping and beer when you’re going to be outside in the cold. I realize that’s probably a deal-killer for many of you, but I’ve found that a cup of hot chocolate with breakfast on a cold morning works just as well for me as a cup of coffee.

Your body also has an internal thermostat called the hypothalamus, which forces a series of actions when it gets cold, and one of the first things it does is make you start shivering. The goal is to increase your level of physical activity, thereby burning more calories and generating more heat. You may also start getting goosebumps – these are to make the hair on your skin stand up and help create a deeper boundary layer of warm air next to your skin. If you’re still cold after that your body begins to reduce the flow of warm blood to your outer layers in an effort to keep your insides warm. Next your breathing will slow down and you’ll probably start breathing through your nose, since that reduces the amount of heat lost during respiration. Eventually your hypothalamus will put you to sleep in a form of hibernation.

The second facet of staying warm is knowing how heat is transferred into and out of your body. There are five possible mechanisms to consider:

  • Conduction – Conduction occurs when two objects at different temperatures are in physical contact with each other and the heat is transferred directly from the warmer object to the colder one. For example, if you’re warm and you lay down directly on the cold ground, your body heat will transfer into the ground; another example is your feet touching the soles of your boots, and you boots touching the ground. This is the most efficient form of heat transfer and will extract heat from your body faster than anything else.
  • Convection – Convection occurs when warmer areas of a gas transfer heat to cooler areas; this is a very poor method of transferring heat, which is why so many types of winter clothing rely on trapped air pockets for insulation. Your body also creates a warm layer of air next to your skin, which helps you stay warm, but the heat in this layer is constantly being transferred to the colder air around it, requiring your body to generate more. When the wind blows against exposed skin it rapidly removes this warm layer and you get wind chill.
  • Radiation – This is when heat is exchanged through the transfer of transmitted energy. For example, you feel warm when the sun shines on you due to the energy in the light from the sun being transferred to your skin and clothing. Warming your hands by a fire is also a form or radiant heat transfer. This is the least efficient method of transferring heat.
  • Evaporation – This is based on the fact that a liquid must have heat applied to it to change to a gas. When evaporation occurs, this heat is taken from the liquid that remains in the liquid state, resulting in a cooler liquid. Your body produces sweat to help you cool down through evaporation, and sweat evaporating in cold air can quickly chill you.
  • Respiration – Every time you breathe in, the air coming into your body is warmed up as it moves down through your larynx and trachea and into your lungs. Every time you breathe out that heat is being expelled out into the air.

One thing you need to be aware of is the myth that you lose more of your body heat through your head that any other part of your body; this was based on a seriously flawed study the British Army did back in the 1940s and has been proven to be false – any exposed skin will lose heat at roughly the same rate. That being said, your head and face are usually the most exposed parts of your body, so you need to make sure you insulate them appropriately.

Outside of freezing to death there are a number of other ways your body can be impacted in the winter:

  • Snow blindness (photokeratitis) is a painful eye condition caused by too much exposure to the sun’s UV rays and can cause permanent blindness. The most common symptom is a feeling of sand or grit in the eyes, but other symptoms can include watery eyes, bloodshot eyes, hazy vision, halos around lights, uncontrollable eyelid twitching, headache and eye pain, and your eyes may swell shut in extreme cases. Snow blindness may cause a temporary loss of vision or even permanent vision loss in extreme cases of repeated exposure. It’s a significant issue when the sun is out and reflecting off of large areas of snow or ice, which can reflect up to 80% of the sun’s UV rays. You need to make sure you have sunglasses or goggle that can protect you from the sun’s UV light, or search the web for articles on how make emergency snow goggles.
  • Excessive sun exposure (both direct and reflected from snow/ice) which can lead to sunburn. When you get sunburned your blood vessels dilate in an effort to increase the amount of healthy blood being brought to the area of the burn to aid in the healing process, which means you’re taking warm blood away from other parts of your body. If you suffer a particularly bad burn, your skin may develop fluid-filled blisters, which is absolutely no fun in extremely cold weather. Always carry some sunblock and chapstick, or completely cover up when you’re going to be out in the sun for any length of time in the winter.
  • Low humidity in the winter can cause dry, cracked or split skin, which can be extremely painful and could get infected. My biggest problem area is my fingers splitting around my nails, so I carry a tub of O’Keefes Working Hands. Low humidity can also significantly increase the amount of static electricity you generate, which can damage delicate electronics (and can be used to see how high a sleeping cat can jump 8-)).
  • Frostbite, which means that parts of your body have actually frozen, starting at your skin and working inward. Remember my earlier comments about caffeine/nicotine/alcohol reducing your blood circulation? The reduction in circulating warm blood to your extremities can be a significant factor in causing frostbite. The most common areas for frostbite are fingers and toes, since they’re farthest from your heart, followed by the nose and cheeks, since they tend to be exposed. There are four degrees of frostbite:
    • First Degree – Superficial surface skin damage that is usually not permanent. Early symptoms include the skin turning numb and possibly swollen, with a reddened border.
    • Second Degree – The skin develops clear blisters and the surface hardens. Later on the hardened, blistered skin dries, blackens, and peels.
    • Third Degree – The layers of tissue below the skin freeze. Symptoms include blood blisters and blue-grey discoloration of the skin. Later on pain persists and a blackened crust develops.
    • Fourth Degree – Structures below the skin such as muscles, tendon, and bone freeze. Symptoms include a colorless appearance of the skin, a hard texture, and painless rewarming. Later on the parts that froze may fall off on their own.
  • Dehydration is another common problem in the winter. Your sweat evaporates quickly, and for some reason this tends to short-circuit a lot of people’s thirst reflex, even if you’re losing as much if not more liquid than you may in the summer.
  • Slippery conditions significantly increase the odds of falls, which can result in bruises, sprains, muscle pulls and broken bones.
  • Chilblains (Perino) are a painful inflammation of small blood vessels in your skin that occur in response to repeated exposure to cold but not freezing air. Chilblains can cause itching, red patches, swelling and blistering on your hands and feet.
Medical Treatment

We’ve covered several things in winter that can cause problems for your body such as hypothermia and frostbite, but it would obviously be useful to understand the symptoms and how these conditions should be treated. Starting with hypothermia, the symptoms include:

  • Confusion, memory loss, or slurred speech
  • Drop in body temperature below 95°F
  • Exhaustion or drowsiness
  • Loss of consciousness
  • Numb hands or feet
  • Shallow breathing
  • Shivering
  • A slow, weak pulse

Any one of those symptoms by themselves may not be an issue, but if two or more present then you should take immediate steps to treat that person. The most obvious (and really the only) thing to do is to warm the person up. You should focus on warming up the core, not the extremities, and avoid rapid changes in temperature like putting the person in hot water. If they have wet clothes get them in some dry ones, wrap them up in blankets or a sleeping bag and start a fire. If you have heating pads or hand warmers, put them inside with the person, but wrap them in some cloth to avoid direct contact with their skin. If you have warm drinks or soup you can give that to them, but avoid anything with caffeine or alcohol.

Frostbite treatment is similar – you need to gently warm the affected area back up. Note that until you can fix the problem that caused the frostbite in the first place you should avoid warming it up, as thawing and re-freezing will actually cause more problems. If the frostbite is on the toes or feet the person should avoid walking if at all possible. Use warm wet heat if possible – avoid direct contact with anything that’s hot, and don’t rub the skin. Cupping the exposed area with your hands and blowing on it to warm it up can also help.

Treating bleeding wounds in cold weather presents some unique challenges. If you need to cut clothing away to treat the wound and you’ll be outside for a while you’ll need to make sure you have some way of repairing or replacing the clothing so the person doesn’t get hypothermia or frostbite. The same applies for irrigating a wound – you need to try to avoid soaking their clothing with water. Having clean (unfrozen) water to irrigate can also be an issue (more details on water later) ; I always carry a sealed 8oz squeeze bottle of clean water and a small clean towel in a ziplock bag in one of my inside pockets to keep it warm, but you could also carry single-use bottles of saline.

Lastly, we discussed how cold can cause vasoconstriction which reduces blood flow, which can slow down healing. Keeping a wounded person warm is critical to prevent shock and promote healing.

(To be continued tomorrow, in Part 2.)


17 Comments

  2. As a person living in northern New England, I deal with some level of Winter for anywhere between 6 weeks and 6 months every year. Really, it’s gotten that erratic where I dwell. I truly enjoy the nature of this site. I will say this, while we are all preparing for what may come, we must try to spend some energy living in the present moment. Winter time outdoors doesn’t have to be only to develop skills for what may come. Winter is it’s own reward, and makes me feel adventurous just being out. Way before I became a prepper, I came to really enjoy the challenge of camping and hiking and being outside in true Winter conditions. While we don’t know what the future will bring, I really believe it’s important to keep a foot in the present moment, and revel in the relative ease of N. American life at current. While many of us have seen frozen wage growth through our adult lives, we still live in opulence by comparison with other human beings on this planet. Get out and stay out, everything is out there.

    1. I’ve been watching the weakening Gulf Stream since the the BP oil spill. It is now so weak in the Northern Atlantic that it cannot regulate the Jet Stream as it once did. I believe the the unseasonable weather, even here in NW Montana is caused at least in part by this. Here is a video that one can see just how obvious the problem is. I would say more, but have to remove some tire chains and fix a flat….

      The North Atlantic’s Mystery Spot
      20,600 views•Aug 15, 2019

      https://youtu.be/Nxt5_-SzAUQ

      1. Btw, I am not a proponent of Global Warming. The solar minimum we are entering is the dominate force. Even in the video, these Climatologists do not discuss the lack of regulation the Jet Stream this now provides, due to this “mysterious spot” in the North Atlantic. The now less unpredicatable Jet Stream may even be the cause of the warming over the North Pole. But that is not discussed. The lack of integrity, and intellectual honesty in our society, has bled over into science. Scientists are only people. The jet stream is not being given the attention it should, by either side in the debate.

  3. Some fun-filled winter injuries I’ve observed:

    -The tough biathlon racer refusing to wear hand protection at -11F. Next day he had huge puss-filled blisters on the tops of his fingers from thawing frozen flesh.

    -Mountaineers with painful sunburn INside their nostrils from walking across snow for hours on a beautiful sunny winter day. Goggles prevented eye damage, but sun reflected upwards did amazing things.

    And one that I experienced: frosted lungs from racing as hard as I could at -10F in a 50K biathlon race. Remember, even if experiencing a TEOTWAWKI winter season event, you could share that semi-permanent injury which is pretty debilitating for subsequent physical activity. In my case for a few years.

    Think Snow.

    1. I have pieces of my ears removed (freeze faster than toes/fingers). Doctors warn another case of frostbite can mean losing fingers/toes/ears. When acclimated below 0f cuts can not bleed until warmed.

  4. Definitely a timely piece. When I woke up this morning and came to work the thermometer said -41 Celsius (which is also 40 below Fahrenheit) With wind chill it’s about -48 Celsius (54 below Fahrenheit) Activities when it’s this cold out are always a challenge – I mean it’s literally too cold to snow. I know a lot of you will have trouble believing that we are out on a job site, working in these conditions. As I keep telling the young guys – It’s not just a job, it’s an adventure!

    Working and living in these temperatures is just a normal winter thing for many of us raised up in Western Canada. The one item that you covered, but is overlooked by many, is snow-blindness. The sun reflecting off the snow can cause temporary, or even permanent damage, and if you are alone, and blind, in cold weather you are as good as dead. The other item to always remember is hydration. The air can be so dry that it will suck the moisture right out of you.

    One old adage that I will pass on when it comes to cold weather: COTTON KILLS
    There are lots of new wonder fabrics out there, but wool is still one of the best options in really cold weather, even if it is a little heavy.

    Looking forward to the rest of the series on this.

  5. In the Swedish Army it was once a court martial-able offence to allow one’s self to become injured, and ineffective because they become battlefield ineffective due to frostbite. This avoidable condition puts the lives of others at risk, because you can not do your job, and protect, or care for your fellow soldiers. There are simple ways to prevent it, and the first step is to be aware of the risk, and be proactive. Act to protect your feet, and hands at the first signs of discomfort. At the first signs of discomfort, change socks, or move to where the feet can be warmed up, or both. Next time, whether inside the house, or out and about, and your feet become chilled, change your socks and see what happens. You will be pleasantly surprised. In a warm house, the feet can easily become damp with the slightest amount of moisture, and can become cold in a warm house. Just before going outside to work, put on dry cold socks and boots, and you’re feet will stay warmer and longer.

    Feet and hands are the usually the most susceptible, and the first to become cold and frostbitten. Soldiers in WW2 would carry up to 4 pairs of socks. Socks can be worn on the hands as well. It take hours sometimes to dry out the moisture making many pairs necessary for rotation, and there must be at least one pair that can be worn. 100 percent wool is the best, and some wool and weaves are better than others. Nose and ears are actually the most susceptible, but usually receive attention right away. Most garments and socks are now wood blends that can be less effective. Look for percentages, and then examine the sock. Much of the polyester/nylon might be located in the area of the ankle, but not in the foot, making that sock acceptable. However, the best socks will contain at least 90 percent wool. Wool will keep you warmer when slightly damp, whereas synthetics will not. If we can keep moisture away from the sock, then it will continue to insulate rather than draw the heat from your foot to the outside of the boot. Water is an excellent conductor of heat. A very small amount of moisture greatly reduces the effectiveness of any sock, including a wool sock to insulate. If the feet become cold, immediately change socks and dry out the first pair.

    Here are some tricks. Layers of socks can be helpful. In a large boot up to 3 layers can be use. The first layer can be a thin synthetic or wool sock, with one or two layers thicker socks over that. Thin wool socks for the summer are still sold in Sweden, and these might be available on line. These are the best, yet 100 percent synthetics tend to be the thinnest and works. The first sock will tend to absorb the moisture, and keep it away from the outer insulating socks. If the feet become cold, change the inner sock or remove it, or replace it. If very cold replace all the socks. And here is a very effective old and forgotten trick to use when all other techniques prove inadequate. Use the thinnest sock, moist or not, and then place the foot inside a plastic bread bag, and then use an outer layer of preferably a wool sock. It is very effective for hours or when exercising, but only use this in very cold and challenging situations, and make sure that the feet are thoroughly dried out in the evening, or risk trench foot and other issues. Do not allow the feet to become too soft. And if the feet become dangerously cold, remove all socks and place the bare feet inside the arm pits of your partner, another old Swedish trick. Warming the foot next to a fire is very dangerous, because the very cold foot can not feel heat. Do not do this. Wool socks are also an advantage, because they will not burn or melt when place near the open flame of a fire. They smolder if in contact with a spark. However, they can be scorched, yet they tolerate high temperatures better, or with out becoming damaged. synthetics should be kept far away from open flames and sparks.

    When out there in rough and primitive conditions, wool is your best friend. In this modern era, where synthetics can be as effective for few hours we are exposed, if used around wood stoves and camp fires, these materials can be a serious hazard if not protected with an outer layer of either wool or cotton.
    Many soldiers have seriously burned when their synthetic clothing caught fire and melted onto their skin, and gave them 3rd degree burns. Cotton as a tight weave, a thin, tough, and protective from flame or sparks, and from the wind and dirt, can be used to protect synthetics or wool. But it because is absorbs and holds moisture, it should not be worn as an inner layer.

      1. Figured u ain’t done :O)

        I’m back in to dry out my clothing and myself before taking a sledge hammer to a rusted on wheel. Changed socks and everything… Of course I’ll be sensible about it, and will attempt to negotiate this situation first. Gotta let the penetrating oil work before using brute force. May loose the rim in the process.

    2. I agree with TR’s sock suggestions. Here’s some additional thoughts:

      Nylon is often added to wool socks to give them durability — it’s a tough fabric and helps minimize holes in heels and the ball of your foot. Less than 8 or 10% nylon is fine if the balance is wool.

      Acrylic is also a common addition to wool blends for socks, but in my opinion it is less useful. I speculate that acrylic is added to lower the cost of the fabric and make the sock feel softer.

      One to four percent spandex is also an OK addition to socks, in my opinion, especially if your socks are long. Spandex or Lycra will help them stay up on your calf all day. I like to put on my thermals and then pull up a long pair of socks over them. I have wool thermals in two different weights — they are teriffic!

      I have found that wool socks sold for alpine skiing are often very thin and can make a useful sock liner when layering socks.

      If your feet get cold from the bottom up, buy thick wool felt insoles, which can really help insulate your feet from the ground. Boots with Thinsulate are also a big help — 200 grams may be OK in the South, but 600 or 800 grams is better for northern climes.

  6. A timely series as we enter a Solar Minima. These past two weeks, we got about 4 feet of snow, more than usual for this area (middle of Idaho) in the last decade, but not in historical context. Things I was afraid would happen during the 1-2-3 systems that went through, like loss of power, did not. I was feeling very content because I’m stocked up, and have had lots of indoor projects to work on, even more than I could possibly do. I have electric baseboard heating, which is great at night in each bedroom, and a propane heat stove in the main area. I realized that both seemed to struggle a bit at keeping the cabin warm enough when the temps dipped down to single digits. So, I’m determined to replace my propane stove with a dual purpose firewood stove so I can heat up food when necessary. The propane stove will keep working during an electrical outage, but the fans that push the warm air around will not. And you can’t cook on top of it. Are there any recommendations for types of wood stoves? I’ve done some research, but would love to hear other’s experiences.

    1. SaraSue,

      I actually don’t cover wood stoves in this series – it’s more about outdoor activities in cold weather. That being said, home heating options and considerations would be a great topic for an article by someone with more knowledge and experience than me.

    2. SaraSue,

      I would not wait, and would purchase and install the best stove you can afford at this time. Get one, including all the high quality pipe you can, even if you cannot install it immediately. A wood stove is central to an off grid, self sufficient life. Without it, one cannot be truly be self sufficient. I’ve built several stoves, yet I am no expert. I would avoid the modern highly efficient stoves that are EPA approved. I suspect it is a compromised design that favors efficiency over reliability. The EPA has mandated and destroyed sensible designs from gas cans, chain saws, to wood stoves. The catalytic part of the design that makes it so efficient will eventually plug up on you.. Go with an older time tested air tight stove that is not one of the high efficient modern types, but of a known durable construction. I would also have several spare stoves, even if they are only antique cast iron, but a stove that I could trust my life on. I collect and repair old stoves too. Stoves do burn out in the back and have issues like anything else, so I have a life time supply that will also be priceless in the future.

      The stove I am currently warmed by was made in 1953, and designed in the 1930’s. I improved the design and made it ‘air tight’. It did have a problem that I had to repair, fortunately a couple of spot welds fixed it. If it fails again, I have another just outside the door that can quickly be installed. I would rather have two ugly old stoves in excellent condition, than one shiny new beautiful thing. A wood stove is so important, that your life may depend on it one day.

    3. SaraSue,you probably have insufficient insulation,your electric utility may have a program to help cover cost of improving insulation(my utility covered 100% cost). Heating cost reduced 1/3,eliminated drafts. Suggest kerosene heater in case extreme cold,power failure-safe/portable/easy to store fuel. Easy way to check is obtain a non contact thermometer(borrow or get cheap from Harbor Freight) and check wall/floor/window temps close to outside vs center of home the greater the distance the greater need for insulation(especially around plumbing)

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