Can I Get Sunburned In Winter?

Our experts bust 19 myths about the fourth season.

Something was off. My face felt tight. Pressure piled in my head like it does when you plunge deep into the ocean or to the bottom of a pool. My heartbeat—rhythmic and steady—thrummed in my lips. I fumbled for my headlamp and sat upright in my sleeping bag, hoping my body would discover some sort of equilibrium.

It was cold on the glacier, which was still blanketed in predawn’s purple vacuum. We were camped on a col high above the pines in the Coast Range, a jagged strand of peaks that splinters British Columbia along the Pacific Ocean. We had spent the three days prior working our way to this spot, alternately skiing, cramponing, ski-cramponing and generally MacGyvering across snow and ice.

It wasn’t that I didn’t believe in the merits of sunblock—that’s silly. But after applying in the morning, it simply didn’t occur to me that I may need more as each day progressed. I was preoccupied with more pressing safety concerns, and without the cue of a blinding sun, the thought never crossed my mind.

And so, as I blinked away the sleep, still nestled inside a downy cocoon in my tent, I didn’t need a mirror to confirm what I already knew: I was in for it. Second-degree sunburns entombed my face, from the top of my chest where I hitched down my quarter-zip base layer in the afternoon, plaited across my throat and up to my cheekbones where my sunglasses sat.

Ultraviolet rays had penetrated through the overcast conditions, magnifying off the snow and reflecting off the ice—soaking into my bare skin like magma. Where we traveled across mountains, literally closer to the sky, the UV index had exceeded summertime levels. And it’s not uncommon. Anyone who recreates outside in winter, whether downhill skiing, snowshoeing or even walking the dog, faces similar conditions. The sun’s rays do not hibernate in wintertime, even if it’s colder or darker outside.

It’s just one myth—that you can’t get sunburned in wintertime—among many this time of year. And it’s the impetus behind the articles that follow. So apply your sunscreen generously and read on as our staffers and co-op members debunk the hardest-hitting myths from the fourth season.

Maren Horjus, Editor

Jump Ahead

In the articles that follow, our squadron of experts sets the record straight on the mysteries of winter.

bears awake in winter

“Bears hibernate in winter.”

Not really. Black bears and grizzly bears enter a state of sleep called torpor. In torpor, a bear’s body temperature and heart rate drop significantly, though it might still wake to eat, drink, relieve itself or even give birth.

Bear sightings are rarer in winter, but don’t be surprised if you see a rogue bruin lumbering through your camp. And continue to pack away your smellables inside a bear-resistant canister.

Read our Backpacking in Bear Country article for more tips.

Sarah Lamagna, REI member since 2011

“Two pairs of socks will keep me warmer.” 

There may be no quicker way to kill a good time outside than cold tootsies. Whether you’re skiing, hiking or running, cold toes can be absolutely debilitating. But the answer is not wearing more socks.

The secret to warmth is circulation—when blood is coursing through your feet (or your hands, for that matter), you’ll be warm. When you add a second sock, then cram your foot inside a plastic ski boot, leather hiking boot or precision running shoe that was sized to fit with a single sock, you create unnecessary compression. That compression limits your circulation, which can actually make you colder.

Instead, consider these solutions:

Ryan Wichelns, REI member since 2017

“Sleeping in the buff will keep me warmer inside my sleeping bag.”

Go backpacking long enough, and we bet you’ll hear this one. The truth, though, is that your sleep sack is engineered to trap your body heat within the down or downlike synthetic insulation, however you produce it (find some tips below).

The most obvious way to retain body heat, of course, is by wearing clothes. The same layers that keep you warm outside your sleeping bag will keep you warm inside of it, so long as you’re not compressing the down or synthetic fill and preventing it from lofting.

Fun fact: Sleeping-bag test dummies wear breathable, moisture-wicking base layers, so if you want your sack to perform at its stated temp rating, at minimum, you should, too. Remember, a sleeping bag is only as warm as the sleeping strategy zipped inside of it.

More hard-earned tips for staying warm in your sleeping bag:

  • While you don’t want to compress your sleeping bag’s filling so much that it stops insulating, you don’t want a ton of dead space in your sack, either. Stuff unused clothes in the empty spaces inside your sleeping bag (usually around the footbox) so your internal furnace has less air to heat. (Bonus: Your clothes will be warmer when it’s time to change and start your day.)
  • Speed up your sleeping bag’s preheat time by doing some exercises before you snuggle inside. A set of jumping jacks or bicycle crunches works great.
  • Fill a 32-ounce Nalgene or other plastic water bottle with boiling water and bring it inside your sleeping bag with you. Pro move? Bring two: Toss one in the footbox and hug the other close to your core.
  • Ahem, keep reading about sleeping pads (below)—and follow with some more tips in our How To Stay Warm In a Sleeping Bag article.

Lily Krass, REI member since 2005

stack sleeping pads for more warmth

“A sleeping bag is for warmth, a sleeping pad is for cushion.” 

When you crawl into your sleeping bag, you compress the insulation. That, combined with the cold ground, is a recipe for a shivery night. So, yes, your pad cushions you from rocks and roots, but its most important job is to help you retain your body heat, which is measured by its R-value.

A sleeping pad’s R-value measures its thermal resistance, or its ability to prevent heat loss. Most camping pads live somewhere between 2 and 6, with the higher numbers being more insulating. For winter camping, especially when your tent is on snow, we recommend pads with R-values of at least 4. Learn more about How to Choose a Sleeping Pad.

But the cool thing about sleeping pad R-values is that they’re additive: Stack a foam Exped FlexMat Plus (R-value 2.2) with a Sea to Summit Comfort Plus SI (R-value 4.1), and your pad situation delivers a winter-ready R-value of 6.3.

Learn more about sleep systems in our Material Science article.


“I don’t need to drink as much water in winter.”

It’s cold outside, you’re probably sweating less, and, frankly, you’re probably not that thirsty. But staying hydrated is just as important come wintertime. Even if you’re perspiring less, you’re respirating just as much and need to replenish that lost water. In general, try to drink half a liter (or roughly half of a 32-ounce Nalgene) of water every hour during moderate activity.

And here’s the biggie: In winter, dehydration is a fast track to hypothermia. When your body lacks the proper fluids, it will have a lower blood volume, which limits circulation. Initially, lower blood flow to the skin will just make you colder—a real bummer during any cold-weather outdoor activity. But if not treated, it can lower your overall body temperature: hypothermia.   


“Drinking alcohol will keep me warmer.” 

Consider alcohol your winter frenemy. As warm and tingly as it feels going down, it’s actually causing your blood vessels to expand. Alcohol is a vasodilator: It makes the capillaries near your skin swell. Momentarily, that allows more warm blood to wash into your skin, near your nerves, making you feel warm. But with a little bit of time, the increased blood near your cold skin cools down, and so do you.

The other hot drink that can get you in trouble? Coffee. Caffeine is a vasoconstrictor, meaning it makes your blood vessels tighten. When that happens, it’s tougher for your body to circulate warm blood to your fingers and toes. The more caffeine in your system, the colder you’ll feel—so lay off that second latte before you hit the slopes.

For a warm pick-me-up, try these options instead:

  • Hot tea: Go for decaffeinated, and let it steep in an insulated bottle while you recreate.
  • Hot chocolate: You don’t want to overdo it on the sugar, but a small bit can provide an energy boost while keeping you warm.
  • Hot water: Pack it in an insulated bottle so it stays to temp, then take a swig when you’re feeling chilled. It’s a double whammy of hydration and warmth. 
  • Food: Body heat comes from metabolizing food. The more fuel you can put into your furnace, the harder and longer your body will have to work to digest it, creating heat. 

Josette Deschambeault, REI member since 2019

how an igloo works

“Igloos are cold.”

Snow is comprised of a lot of air—and air is an incredible insulator. When a bunch of people hang out inside an igloo, their body heat is trapped in the snow blocks, where it begins to insulate the area, much like your puffy jacket or sleeping bag.

If the ambient temperature really starts rocking, the inside walls of the igloo will begin to melt, ostensibly sealing the shelter from outside elements and making it even warmer (and stronger, too). Another factor that makes an igloo a comfortable place to hunker down? For starters, its architecture. Like a domed mountaineering tent, a rounded igloo shrugs off heat-sapping gusts.

For the warmest results, create an elevated platform inside the igloo for your sleep area. (Remember—heat rises.) 


“Don’t sweat in winter.” 

The prime function of sweat is to cool the body down. When it’s hot, this is a good thing. In winter, however, when ambient outside temps are freezing, this can spell disaster. Suppose you’re skinning up a steep hill or breaking trail in waist-deep powder—you’re going to perspire, perhaps profusely. When you slow down or stop, the sweat that remains in contact with your skin will lower your body temperature as it evaporates. That’s going to be a good thing for however long it takes you to regulate, and then it can become a fast track to hypothermia.

But not sweating also has its disadvantages. In the not-so-distant past, there was a prevailing wisdom in the outdoor community about heading sweat off at the skin-pore pass. Folks would slather antiperspirant, which works by plugging the sweat glands, on their armpits, chests, feet, groin area and other clammy places.  

While this sweat-mitigation strategy may have borne some minimal manner of fruit, there were predictable issues. First, sweat does more than cool the body. Sweat—which consists primarily of water, with traces of ammonia, urea, salts and sugar—rids the body of toxins. Research shows that it can also flush the body of harmful bacteria and unneeded calcium and salt. It can also help protect against infections caused by scratches, bites and stings.

Second, it wasn’t all that effective. Antiperspirants were designed for more languid settings. When you work hard, pressure builds up in those clogged sweat glands and eventually ejects the antiperspirant like a cork shooting out of a champagne bottle. The body needs to sweat, even when it’s cold.

That makes wearing the right layers all the more important.

Layer like a pro:

Base layer:

Worn closest to your skin, this layer should have a snug fit; it wicks perspiration away from your body to prevent your core temp from cooling.

You have two choices when it comes to materials: wool or synthetic. Wool has one of the best warmth ranges of any fabric, thanks to the natural crimp (or zigzag) of its fibers. It traps air in tiny pockets which warms up fast from body heat. It will still insulate when wet with sweat. Synthetic, or polyester, base layers are often lighter and more breathable than wool, making them great at both wicking sweat from your skin and drying quickly. But they aren’t as resistant to body odor and won’t insulate when wet.

Never, ever wear cotton base layers. When cotton gets wet, it stays cold and takes forever to dry—a perfect recipe for hypothermia.

Mid layer:

Your warming layer, the middie acts as your insulation. There are plenty of options—a down jacket, a synthetic puffy, a fleece, a wool sweater, whatever—just make sure you wear it over your bibs or suspenders. You want to be able to remove it when you start sweating.

Outer layer:

Your shell—whether soft or hard—blocks wind, rain and snow. For strenuous activities, wear an uninsulated shell so sweat vapor wicked from your base layers can more easily pass through and evaporate.

Find the perfect layering schematic for you with our handy-dandy guide: The Art of Layering.

M. John Fayhee, REI member since 1976

yetis stretching before running

“I should stretch before running.”

This one is nuanced. Think of your muscles like taffy. In mild or hot weather, it’s pliable and soft. When it’s chilled, however, that candy is harder than a brick wall. If you tried to bend it in half, it’d snap. Your body operates in the same way.

Standing with your leg propped on a fence or sitting in the butterfly position—called static stretches—are not going to help you feel properly warmed-up before running in cold weather.

Instead, you’ll want to focus on dynamic, or active, stretches that mimic actual running. By engaging your joints and muscles in this way, you’ll increase your heart rate, raise your body temperature and teach your non-active muscles to relax. Implement five minutes of dynamic stretching before your cold-weather run to best prepare your body for go time.

Dynamic stretches to try before your run:

  • High knees: Jog in place, raising your knees to waist-level for about one minute.
  • Butt kicks: Jog in place, raising your heels to bum-level for about one minute.
  • Skipping: Exactly what it sounds like, but we recommend incorporating some high knees and really pumping your arms to engage more muscles.
  • Leg swings: Bracing yourself against a wall or fence with one outstretched arm, swing your inside leg forward and back, parallel to the wall or fence. Keep your leg as straight as you can, and try 10 reps per side.
  • Arm circles: With your arms outstretched at shoulder height and palms facing down, create 6-inch circles with your fingertips. Try 30 seconds forward and 30 seconds backward.

But don’t cancel static stretching just yet. It’s still a great way to lengthen and relax your muscles after your run, increasing flexibility and minimizing the risk of injury.

Learn more (and peep dynamic stretching GIFs) in our Stretches for Running article.

  Heather Balogh Rochfort, REI member since 2008

“I need fat skis (or a fatter snowboard) to ride powder.”

While it’s true that a wider surface area will keep you on top of the snow better when you’re not moving (think: snowshoes), the key to flotation when you’re cruising downhill has more to do with the profile of your equipment.

When the tips of your skis or the nose of your board curve upward like the rails on a rocking chair—called “rocker,” “early rise” or “reverse camber”—you’ll float better at speed. Your skis or snowboard will act more like water skis or a wakeboard, skimming over the surface with less edge contact.


“My ski boots should hurt.”

We won’t speak for racers or pros, but this simply isn’t true for most of us. Yes, downhill boots are clunky and made of hard plastic, but since every single turn and movement in skiing starts with your boots, you should have a good working relationship with them.

Here’s how: First learn how ski boots should fit. They should be snug, but you should be able to wiggle your toes. Always try ski boots on in a store before buying, and know that heat-molding options abound these days, so you can manipulate the liners (and sometimes even the shells) to fit your specific feet. (Yes, we do this at REI. Find services near you here.)

Second, don’t be afraid to mess with your setup once you get going. Changing the thickness of your socks can work wonders (just don’t wear two pairs, of course), as can tweaking the tightness of the various buckles.

And remember that there’s a break-in period for ski boots. But if you’re still experiencing pain or nagging discomfort, refer to this chart to try to find a solution.

What hurts?What does it mean?Possible solution
Toe bang (pressure on big or second toe, which can lead to lost or black nails)True, your boots might be too small, but we bet they’re actually too big. When your boot is even half a centimeter too long, your stocking foot will slide forward when you initiate a turn. Just half a day of this repeated motion can be a kiss of death for a toenail.If your boots are too small, try a thinner sock or footbed. If your boots are too big, try a thicker sock or footbed. A professional boot fitter can also explore options like blowing out the shell or trying a spacer.
Shin bang (bruised or bumped shins)This is probably another case of too-big boots. (Or an indicator that you’re skiing in the back seat.) When you ease out of a turn in a boot that doesn’t secure your heel, that tiny lift jolts your shin into the front of the ski boot. Like above, do it enough times and you’ll earn your shin a big ol’ contusion.Try a thicker sock with body-mapped padding at the shin (like the Smartwool Performance Ski Full Cushion OTC). If that doesn’t work, consider heel lifts to lock your foot in place and minimize movement. Failing that, contact a boot fitter.
Arch crampsYour arch is probably collapsing due to lack of support in your ski boot.Snag yourself a pair of more supportive footbeds.
Cold feetThis can be a byproduct of genetics, poor clothing choices, extremely cold weather—or too-tight boots. If your boot is too small or ratcheted too tightly, it can compress your foot and prevent proper circulation.First, see what happens when you increase circulation to your feet: Loosen each buckle a hair and release pressure on your power strap. You may want to also try thinner socks and knicker-style base layer bottoms that hit above your boots like the Smartwool Merino 250 3/4 Bottoms (the less fabric for bunching in there, the better). Failing that, try a heated insole like the Hotronic Foot Warmer Power Plus Custom S4+ Set.


“Moguls are made by machines.”

No. Unless we’re talking competition-grade courses, the standard bumps you encounter at resorts are created by folks simply following each other’s tracks. Moguls grow in size (and the channels between them become more severe) the longer the terrain goes without being groomed or receiving new snow.

Skiers, want to experience something wild? Try tackling a bumped-out run at Deer Valley, Alta or Mad River Glen—which disallow snowboarders. The routes between the moguls will seem much more intuitive and, dare we say, almost as though they were machine-made.


places to keep your hands warm

“Rubbing my hands together will make them warm.”

This really only works on still-warm hands. If you’ve already lost circulation or are experiencing the early stages of frostbite (numbness, waxy texture or loss or change of color), friction won’t generate enough heat to make your hands warm again. In such cases, tuck your bare hands into the vascular (read: warmest) areas of your body, like your armpits, behind your knees around your midsection or between your thighs.

Wind-milling your arms or shaking your wrists to force blood flow to your fingertips can also work well.  


“I must wear my beacon in my chest harness.”

When you buy an avalanche transceiver, it comes with a holster that has cross-body and waist straps. The harness is meant to be worn on your person, over your base layers or bibs and beneath your shell. But in most cases, your beacon can be worn without the harness, as long as it’s (1) protected, (2) accessible, (3) attached to you and (4) comfortable.

  • Protected: Your beacon needs to be shielded from the elements and tucked away somewhere where it won’t be affected in, say, a crash or fall. In this way, it’s a lot like your phone or camera—you don’t want to smash your gadgets.
  • Accessible: There’s a reason you can’t just stuff your beacon away in your pack—it needs to be at the ready. In the event of a slide, you must be able to quickly switch your transceiver to Search mode. If you’re digging through your pack or delayering to access just the right pocket, you’re wasting precious time.
  • Attached to you: Your beacon should be tethered to a secure point on your harness or person so it can’t fall out or drop when in use.
  • Comfortable: You don’t want your beacon to be an annoyance or restrict movement when you’re touring.

If your pants have an oversize bib or kangaroo pocket or thigh pocket that’s positioned more on the front of your leg than near the hip, these can be nice places for storing a beacon. If the manufacturer included an attachment clip or leash inside the pocket, then chances are it was designed for such use. (No clip? Use a basic slipknot to loop the beacon’s leash through the zipper pull of your pocket.)

Whether you keep your beacon in a harness or pocket, knowing how to carry it is important: Always keep the screen facing you (so it’s harder to damage) and at least 20 inches away from other electronics, which can create electromagnetic static. 


“I must turn my phone to Airplane mode when using a beacon.”

Last avalanche transceiver wonk, we promise.

Somewhere along the road, guides and backcountry pros started telling skiers, splitboarders and snowshoers to switch their phones to Airplane mode before leaving the trailhead. But here’s the rub: It’s not the radio signals sending your texts and Instagram notifications to your phone that will interfere with an avalanche transceiver’s ability to search. It’s the noise—or static—emitted by your phone’s operating internal electronics.

So as long as your phone is at least an arm’s reach or so away from your transmitting beacon, both will operate as intended. Good news for iPhone shutterbugs.


yetis studying layers in a snow pit

“A good snow pit will tell me everything I need to know about avalanche conditions.”

If you want a lot of information about one specific angle on one specific slope, knock yourself out and dig a snow pit. But do not treat your hole as a one-stop-shopping test for avalanche danger. A snow pit should be taken as a single piece of evidence along with the avalanche forecast, the current weather, observations made along the way and the gut feelings of others in the group.

Brush up on other warning signs with our Avalanche Awareness series, and take a real class before venturing into heady terrain. REI offers primers, and the American Avalanche Association endorses courses across the country.


“Skiing a resort’s sidecountry is safer than skiing backcountry.”

Perhaps the actual myth worth busting here is that the sidecountry—sometimes called “slackcountry”—is safe at all.

“Sidecountry” is a loose term that generally refers to out-of-bounds terrain you can access from the in-bounds area of a ski resort. Its draw is that it offers the benefits of backcountry terrain—like untouched powder, fewer or no people, bragging rights—while being easier to get to. But just because an area is adjacent to a patrolled, managed area, does not make it safe. In the 2020 to 2021 ski season, 17 skiers and snowboarders were killed in avalanches, four of which were coined “sidecountry accidents” by the Colorado Avalanche Information Center.

So let’s call the “sidecountry” what it is, which is the backcountry. Don’t go if you’re untrained or lack the proper safety equipment and know-how. Treat it like full-fledged backcountry terrain, because that’s exactly what it is: unpatrolled, unmanaged and wild.

Read more about reducing risk in our How to Recognize Avalanche Terrain article.


“I can trigger an avalanche by yodeling.”

Avalanches release with pressure—whether that’s from a skier’s body weight or a controlled explosive inside a resort. The human voice doesn’t create enough pressure to stress the snowpack. Take our word for it, or indulge in this study.


All illustrations by Sarah Neuburger, REI member since 2011.

Have any more winter myths we should look into? Leave your quandaries in the comments for volume two.