Qfyilyi

This question is prompted by a real accident, in which a young, healthy and experienced hiker I knew was found dead from hypothermia ridiculously close to civilization.

The assumptions behind it: a hike in winter conditions in a temperate climate zone (Europe), can be below or above the tree limit. The hiker plans to sleep in serviced lodges, or to go up and down on the same day, so has no tent or cooking equipment along. It is not too far in the wilderness - if the hiker calls a rescue service and can somehow submit exact coordinates, rescuers can reach the hiker in time. The hiker has no experience building a shelter out of branches, or some kind of iglu-like construction. The hiker envisions an easy walk along a marked path, but the weather turns problematic (e.g. a snowstorm, or fog) and he or she loses the way. Cell phone coverage might exist, but is likely to be patchy and weak, and probably without mobile Internet or reliable GPS.

I saw that there are questions about actions one could take, but I would like to ask for a list of items one would have to carry to prevent hypothermia and death, and have a reasonable cost (most people I know cannot afford a satellite phone, for example). This would include items which make it easier to find one's way again, to communicate with rescuers, to prevent hypothermia in the short term (like the energy bars mentioned in the linked question) and to preserve enough body warmth (or maybe there is a heater option?) to survive for a whole night, if needed. Also, the package should be small enough to allow for an enjoyable hike when everything goes well.

As usual, skills are the lightest and most effective thing one can carry. From how to bushcraft useful things from natural materials, to clever ways to satisfy needs like signaling or navigation, to keeping a healthy state of mind.

Nonetheless, some useful items greatly increase chance of success / reduce chance of suffering. The less skills, the more reliance shifts to items. Because items aren't always reliable, can weigh down a hike, and sometimes call for special skills anyway, much better to start with skills! Now onto the items, a kit I've carried in very remote, very cold woods through good and bad:

Think in terms of elements, and in terms of marginal benefit. For example, carrying an axe is nice if you need a lot of wood, but it's very heavy and could be improved or worked around with a knife, downed debris, or even a folding saw. Therefore an axe has little marginal benefit - carry a knife instead.

Summary of Gear (the TL;DR if you want ot skip details)

When I lay all this gear out on a table it is not much. A zip-lock bag of fire stuff rolled up; my water bottle/cup in a belt-pouch or backpack; a trauma kit with water tablets in another belt-pouch or backpack; tarp-poncho in its own pouch plus a zip-lock with rope and some bush-shelter-odds-and-ends all stored in a backpack; basic navigation/signaling tools and a knife in my pockets/belt. I should weigh it but I'd guess it's all under 5lbs not counting liquid water and clothing.

Fire

Redundant, rugged, and lightweight. Starting a fire with numb feet and fingers is not fun and it is easy to lose clear thinking during this process. Carry a light water-tight container (e.g. used zip-lock bag) with items discussed in Given limited space and weight what should I carry to get a fire going with damp wood?

• Storm proof matches


• at least two lighters, better yet if one is designed to be 'storm proof'


• fire starters (e.g. eco-friendly ones made of wood wool and flammable wax)


• Flint and magnesium stick


• Fixed-blade knife, probably at least 3" blade, the sharper and closer to full-tang the better


• Extra knife. "Two is one and one is none" - and you do not want to need to improvise a cutting tool in the cold winter woods!

This entire bag can weigh very little. Before I go out I double check there's plenty of matches, at least a lighter, more fire starters than I think I'll need for a few days out there, and a flint stick. Then I stuff it in the bottom of my pack - if I'm starting a fire I can empty my back and stay put for a bit.

Water

Best to go out hydrated, carry water in yourself. Also carry a liter to start a hike with. Some people like carrying a single 1L container, others multiple small pouches, I don't think that matters. What matters is that you have a container you can boil water, preferably without poisoning yourself. I carry a nested hard plastic container + steel cup. I also carry ~6-12 water purification tablets in my first-aid kit - very light, rarely used, but you'll be glad you have them if you need them.

Shelter

Your clothing is the key here, and layers are the key to that. You should be able to go from sauna to frozen outdoors with the clothes you carry on your back or tied to your pack or waist.

When I'd wander in very cold remote woods I'd wear: thermal pants and top, rugged pants, insulated overalls, 2 thin-ish warm tops, insulated wind-breaking jacket, scarf/shmagh, bandanas in my pockets/pack, balaclava, beanie, thin gloves with dexterity, thick wind-breaking water-resistant mittens, thick and/or 2 pears of socks, insulated water-resistant boots.

This pile of clothing will make a big difference if you simply curl up in a ball under some natural shelter. If you are improperly dressed, your situation is much worse. But also don't let your clothing encumber you too much, and be careful not to sweat.

Lastly, for a day hike you don't want to carry a whole tent or whatever, but some basic components save you a lot of trouble if you are forced to overnight. I am a huge fan of carrying a lightweight tarp, better yet a poncho-tarp. That plus plenty of rope, and if you can bare it carrying >6 tent stakes and some carabiners can help too. With that pound or two of gear, and your tough knife from the fire-kit, you can construct pretty solid make-shift shelters in just 2-4 hours if you are below the treeline.

Navigation and signaling

I used to keep it simple with a good compass (which includes signaling mirror) and topographic map. I'd also have an emergency whistle on me somewhere. Working in the woods I now carry a radio and/or GPS emergency beacon but I didn't used to.

First-aid

Pick-up a light-weight trauma kit and keep that in an accessible part of your pack. Accessible so that you can access it quickly while panicking and injured, and in a simple place to describe so you can communicate its location to someone else in distress if needed. For intentionally longer trips, different/more first-aid is called for, but for day trips a trauma kit will do. Maybe a basic manual booklet too, some kits come with that.

Add some good cold-weather camping snacks to first-aid in case you get hungry out there :)

I have spent significant time in the backcountry in the winter. Last year I did an early season through hike of the Continental Divide Trail, spending months living in the snow.

Below is a list of some items I'd recommend bringing if you're going on a casual hike in the winter. You should not bring all of these at once. Consider the conditions, your objective, your risk tolerance, and your experience when choosing which of these are appropriate.

• Waterproof & windproof outer layer


• 
  Warm mid layer: Ideally something like a fleece that works when wet. Down is okay if there's no chance of it getting wet.


• Moisture-wicking base layer


• 
  Long pants or tights: They don't need to be waterproof unless conditions are really bad.


• 
  Sunglasses: ⚠️ Snow blindness is no joke.


• 
  Long warm socks: I got frostbite on my ankles once because I was wearing ankle socks. You're probably smarter than me on that front.


• 
  Waterproof mittens: I wouldn't bother bringing any gloves that aren't waterproof into the backcountry.


• 
  Scarf, buff, or neck gaiter: If the wind picks up, you're going to want something to cover your face. It doesn't need to be too bulky.


• 
  Gaiters: Wet feet can escalate into a serious problem. If you expect to be walking through loose snow for more than 8 hours, gaiters are a very good idea.


• 
  ResQLink Personal Locator Beacon: Satellite phones are expensive. The next best thing is a PLB. Keep it in an outside zippered pocket of your backpack. Should you find yourself in a life or death situation, this can send out a distress signal via satellite and quickly summon help. (~$200, no monthly fee)


• 
  Microspikes: If there's any chance of encountering icy conditions, bring some microspikes. They're small and light. If you aren't on high angle slopes they're as good as crampons. ($60)


• 
  High calorie snacks: Pick something that isn't going to freeze into a solid mass (e.g. potato chips, crackers, bread)


• Foil blanket


• 
  Sleeping bag, ground pad, and bivy sack: Even if you don't plan on spending the night, these may be worth bringing in case you get stranded somewhere.


• 
  Headlamp: ⚠️ Always always always bring a headlamp.


• 
  Camp stove, tea, hot chocolate: The ability to heat water and/or melt snow may be the difference between a dangerous situation and a relatively pleasant situation. Stop for a hot beverage if morale is starts getting low. :)


• Map and compass


• 
  Offline maps on your smartphone ⚠️ (e.g. Gaia GPS (Fair disclaimer, I work at Gaia GPS))


• Extra socks

The safest concept is to always plan for the worst case. Of course, best practice varies according to context. Whether you're going solo or in a group, the equipment will change. Same goes for the different seasons. But generally, plan for slightly more than what you expect; i.e. if you're going on a day-trip, carry at least enough to overnight outside.

In your particular case, a solo hiker in the winter, it becomes somewhat of a tradeoff. In a group, for a day-trip, there should always be someone carrying a sleeping bag in case someone gets injured and immobilized. That is alongside an emergency kit. It adds up quickly in bulk and weight, but when you can divide it among a group, it's easier to manage.

Carrying a sleeping bag becomes slightly cumbersome for one person on a day-hike, so it's usually replaced by an insulated parka. If you can keep your core warm, you can last a while. Anyway, the parka usually gets used if taking longer breaks, provided the hiker doesn't overdress to begin with.

As for an emergency kit, it doesn't need to be that large. A means to start a fire and a good quality space-blanket already cover the most essential pieces of equipment to overnight in cold weather. Those take up almost no space in a pack and there is no reason not to carry them.

I personally do solo-hike in -25°C weather regularly and my 32 liter pack is pre-made, hung in the gear-room. It's a bit overkill as I carry a way too large first-aid kit although it's more in case I need to help others. Strapped on the side is a thin 5mm EVA sleeping pad which is part of the E-kit. Then the rest is clothing, which usually consists of upper and lower waterproof outer layers, a down parka, two pairs of insulated gloves (in case one gets waterlogged), multiple pairs of polypropylene liner gloves, a pair of spare liner socks, plus 2L of water, some dry snacks (nuts, fruit bars, cheese), etc. I know I could overnight with that gear. It wouldn't be comfortable, but enough to stay warm.

The most important part of the puzzle though is not necessarily what I carry but what I know about using it. Any serious outdoorsman/woman should consider taking wilderness safety/first-aid courses and practice/revise their knowledge regularly.

First: buddies. Solo activities are inherently riskier.

Not that's out of the way, what kit is practical?

Extra insulation and extra wind/waterproofing. This may be just one item, but it's more likely to be a foil blanket, extra mid layer, and survival bag. If you stop moving, you stop generating as much heat, so you need insulation. The extra mid layer, fleece or similar can be used simply for comfort, while the foil blanket is light and can be worn under the outer layer of clothing or over the top. This can be left with a casualty if you go to get help. The bright orange survival bag is also a signal that shows up well against snow or vegetation. If another hiker sees a survival bag, they're likely to go and check.

When kayaking in the winter I carry something slightly better than a survival bag but also bright orange - a small group shelter, which can also be wrapped round an individual. I have a foil blanket as well. I also keep a foil blanket in my compact first aid kit for distance cycling, when space and weight are at a premium (except in the height of summer).

When winter kayaking and often when winter walking, I carry a thermos of hot drink. It's not meant strictly for emergency use, but tends to be started after the toughest part of the day and finished at the end of the trip.

As well as slightly more snacks than I expect to want, there's something to eat in my emergency kit (a long life snack bar of some sort).

It's not unknown for me to grab my entire kayaking emergency bag for a day hike in winter. That adds a first aid kit, head torch (useful if delayed until after dark) and light stick (a casualty is much easier to return to after dark if they've got a light source, and it's very comforting). There's other stuff in there that's less useful for hiking, but it doesn't weigh much and I prefer to keep the kit intact.

The ability to get exact coordinates and send them to someone useful is important. SMS can still often get through with a patchy signal, as it should wait until it can connect, but recently we had more luck with a messaging app that sent as soon as it got a data signal (not an emergency, but good practice for one - two members of one of our two kayaking groups didn't do as much river as their boats did, but communication reunited then with most of their kit without excessive hanging around on river banks).

Here's a pic of a small emergency kit I put together (plus the knife, compass, and whistle that were part of the 'normal' gear). Granted, this was for a summer (August) hike in the White Mountains of New Hampshire, USA. However, getting lost above treeline the weekend I was there could have easily killed someone from hypothermia. So, even though this is my typical emergency kit that I carry with me (and I could make work given my experiences), it might not suit your needs for winter hiking. If I were doing more winter day hiking, I think I would bulk up my kit.

*see below for more details of the trip and the thought behind this kit

Waterproof bag to hold it all

• Protects the kit, plus you could gather water in it. In theory, if
  you can hold water in a container, you can boil the water. But, I've
  included some water treatment pills in the little pill holder. Also,
  nice little non-weight-bearing carabiner.

Heat Reflective Poncho

• Better than nothing. Wet is way worse than cold.

Water / weather proof matches

• You can't really see from the pic, but these are the type that
  should burn even in stiff winds and / or if they've gotten wet. Even so, they are in a water-'proof' container

Tinder / Water (treatment)

• Wax-infused cotton tabs for the tinder. Iodine water treatment pills
  (which I sealed inside of bits of a plastic straw to water-'proof').

390 kcal 'Meal Replacement' Bar

• I had to punch a hole in the foil wrapper to let out some packaged
  air; I resealed with duct tape. Fits inside of the soap holder /
  first aid kit.

First Aid Kit

• 
  

  Contains:

  
  
  
  
  
  1. Another whistle
  
  
  2. Signal mirror
  
  
  3. Alcohol prep pads
  
  
  4. band-aids
  
  
  5. gauze pads
  
  
  6. duct tape
  
  
  
  

Paracord

• I think I did about 30 feet. It's never enough, but it might do.
  Worst case, it burns, too.

All together, it weighs 14 ounces (about 0.3-0.4 kg) and is about the size of 2/3 of a Pringles can. I keep saying water-'proof' because, in my experience water is so damn hard to keep out! Ain't nothing waterproof, I don't care what they say!

edit

*Further details: This was a trip where I (a reasonably experienced and trained backpacker) took my friend and his teen-aged daughter to backpack up to shelters, drop gear, and day hike up to the summit. Each one of us had our own kit; the point of this kit was that this was the backup kit for us when we day-hiked from the shelters to the summit.

A general note about weather in the White Mountains, even in August: It was nasty! (50+ mph winds; rainy, misty, nasty weather; just above freezing at the Hermit Lake shelters where we stayed, which was below the tree line). In fact, the weather was so bad that a AT thru-hiker (super inshape dude) we shared the shelter with literally could not walk against the wind up on the ridge. After my group decided to abandon the ascent, he tried, failed, and met back up with us. So, even though it was one of the hottest months in a very hot year, it was very dangerous weather where I think I could have used this kit to save myself, but I am damn glad that I did not have to!

To start with, there is no such "list" which can adequately cover your question- every trip is different, every scenario is variable, and winter is such a broad period that regions have completely different challenges ("winter" in the Northern Hemisphere happens in a different part of the calendar year than it does in the Southern Hemisphere, and January in the Front Range of the Colorado Rockies varies drastically from March in the same location varies drastically from the Western Slope 100 miles West). Additionally, hypothermia can easily be suffered in July or August (at 2000m elevation, in July temps can be under 10C at night, even start dropping in the 10-15C range by dusk).

The only constant item you will always bring with you is your brain; that may sound flippant or impudent, but I mean it quite sincerely. Going into the wilderness without proper knowledge and education is the first potentially life-threatening mistake you can make (you referenced not knowing how to erect improvised shelter). Next, if you lose your head and start to panic, you will be in a world of hurt; education is the foundation here.

Have you taken a Wilderness First Aid course? Are you aware that, if you require assistance by a Search and Rescue team, it can take over an hour just to transport you 0.75km (0.5mi)- not counting the time it takes to call them, SAR to organize and respond, response time, travel time to you, patient evaluation, patient package for transport, handoff to EMS personnel, transport to hospital? Do you know how to handle an injury in the backcountry and the exponentially complex nature of something as simple as a blister which wasn't managed properly when you are in the backcountry versus front country (e.g. your house)? Do you have a proper first aid kit and know how to use it?

Next is basic survival skills. This doesn't have to be an expensive class by any means. There are usually groups which will teach basic skills in wilderness survival and how to keep warm and dry.

As for gear, backcountry medicine and survival is 90% improvisation, so a good class will teach you goal oriented skills and how to improvise with the items you always carry. ab2 referenced trekking poles and I agree; I always walk with them (when I was a guide one of the guys on my team used to call them "wussy wands" and I love the term- especially since he now uses them). They will reduce strain on your back, knees and ankles and they are incredibly versatile- splints for instability in limbs/joints, improvised shelter building, etc. a base list might include (but is not limited to):

• Aforementioned trekking poles
  emergency blanket (the heavy duty kind such as those made by SOL, not the cheap limar "space" blankets)


• Cravat (x4)


• SAM splint


• Fire starter (flint and steel and nesting material- practice and know how to use them)


• Signalling materials (I like the Silva Ranger compass with mirror and sighting slot, Storm(tm) whistle, and the flint and my fire building material is also for signalling)


• Navigation tools (manual, NOT your phone or GPS, and know how to use it- the compass serves double duty here, and carry a map of the region in which you a traveling)


• First Aid kit; a real one- no off the shelf first aid kit I've found is sufficient or effective. They're usually "150 parts" 145 of which are useless in the backcountry, or made for x number of people for y number of days and are way overpriced and full of a bunch of junk you won't use, missing stuff you need, and have a little first aid book which won't do you much good in an emergency ("let me see, you're bleeding out...bleeding..bleeding...ah! 'uncontrolled bleeding, what to do' page 18, 72, 101...okay..give me a minute to look that up..."). Take a WFA or WFR course, know how to use it and what to do.

This may sound like a lot and very expensive (and some may say overkill for a day hike), but the listed items actually aren't that substantial in size/weight and a day hike is something which seems like a simple activity which doesn't require more than shoes and a water bottle, but it can quickly become life threatening.

Permit me to relate an anecdote here:

A couple of students of mine were enjoying a day hike on a trail just outside Boulder, Colorado (about 30 minutes from the hospital) when, about 1.5mi (~2.4km) in they encountered a young lady on her way to the trailhead to call for help (they were in a canyon and reception was spotty). She said her friend had "fallen" and they was hurt so, having recently completed their Wilderness First Aid course, had their first aid kits with them and went to check on her. The patient had fallen 20ft (6m) from a rock and was in pretty bad shape. The two young ladies requiring assistance were on a simple day hike in July in a well known area close to town, and were taking a short break on an overlook to take in the view when the patient slipped and fell. it took 13 hours to get her to the hospital. They had no first aid training, no first aid materials (just hiking shoes, snacks and water) and no survival materials (shorts and t-shirts for summer weather). Worst of all, no training of any kind and so no ability to improvise with what they did have. Luckily, the friend did have her cell phone, kept her wits about her, and knew enough to make sure her friend was breathing and went for help. They just got lucky in that some trained and well prepared people were on the trail ready to render assistance.