The Flatlander's Guide to Colorado

what to wear

When you're in the mountains, layers are always the way to go. There's a popular saying here in Colorado- "If you don't like the weather, wait fifteen minutes." This is incredibly accurate and you need to plan accordingly. The weather can and will shift in an instant, and up in the mountains it can snow any month of the year. When hiking in the mountains, how you dress should change dramatically between summer and winter, because the risks and conditions are very different in each season.

summer

In summer, the main challenges are heat, sun exposure, sudden storms, and large temperature swings between day and night or lower and higher elevations. Clothing should focus on breathability, moisture management, and sun protection while still preparing you for cold or wet weather. Your best bet is to layer tank tops or t-shirts with button downs- I love Columbia's SPF shirts, they're super comfortable and lightweight. Even on hot days, a light insulating layer such as a thin fleece or puffy jacket is important because temperatures can drop quickly when clouds roll in or the sun sets. A lightweight rain jacket or wind shell is essential, since summer thunderstorms are common in mountain areas and getting wet can lead to hypothermia even in warm months. For every thousand feet you go up in elevation, the temperature will drop by 3 to 5 degrees. A heavier layer is just a good thing to have in general, even if it never leaves your backpack. If it gets windy up on the side of a mountain you're going to be really glad you brought it.

On the bottom, it doesn't matter if you're wearing pants or shorts as long as you're wearing something. Just do yourself a favor and don't wear jeans on a hike. Besides the fact that you're more likely to get heat rash, if it starts raining and they get wet you're going to be so uncomfortable. They will stick and chafe and do absolutely nothing to keep you warm. Sincerely, someone who went on a horseback ride in jeans- in July- and got rained on, then got hailed on, then couldn't feel her legs for an hour.

Sun protection matters more at altitude, so a wide-brim hat, sunglasses, and sunscreen are key parts of what you wear, not optional extras. The higher you go, the thinner the atmosphere is going to be in between you and that big ball of radiation in the sky. 15 SPF isn't gonna cut it. I would go 50 SPF at minimum, and reapply multiple times during the day. Don't skimp on the hat, either, unless you want to know the torture that is a sunburned scalp.

For shoes, hiking boots are the way to go. I understand that not everyone has a pair, but if you live in Colorado and want to go hiking regularly it's worth the investment. I swear by my high-top Merrell Moab's. My dad likes Oboz. It's all about what feels right for you, so do yourself a favor and try them on in store. Get them fitted and try a couple different brands. If you don't have hiking boots and aren't in the position to get some, running shoes will work as long as they've got good treads. No vans, no converse, and avoid open-toe sandals at all costs. Anything is better than sandals. With your shoes, wear thick, comfortable socks to avoid blisters. Wool is best, if you can get them.

Winter

In winter, dressing for mountain hiking turns into a game of managing heat without getting tricked by it. You’ll spend part of the day working hard and generating a lot of body heat, and other moments standing still in biting wind wondering how it got so cold so fast and why on earth you decided to do this in the first place. What you wear has to handle both extremes without letting sweat or weather sabotage you.

Everything starts with the base layer, which is basically your personal climate control system. A warm merino wool or synthetic layer helps trap heat while pulling sweat away from your skin. This matters more in winter than any other season, because moisture is the enemy. If sweat cools or freezes, your body temperature can drop quickly, even if you’re surrounded by warm layers. The goal is to stay just warm enough while moving, not cozy. Feeling slightly cool when you start hiking is usually a good sign that you won’t overheat once you get going.

On top of that comes insulation, and this is where winter hiking gets customizable. Fleece works well while you’re moving because it breathes, while a thicker down or synthetic puffy jacket is your reward for stopping (along with a snack). Many experienced winter hikers carry a “stop jacket” that only comes out during breaks, and it can feel like flipping on a heater when the wind is howling. Synthetic insulation has the advantage of still keeping you warm if it gets damp, which can be a lifesaver in snowy or humid conditions.

Your outer layer is your shield against the elements, and in winter it needs to mean business. A proper shell blocks wind, snow, and freezing rain, and it often matters more than how thick your insulation is. Wind in the mountains can slice through thin clothing and steal heat faster than you expect, so a windproof jacket and pants make a huge difference. Ventilation, like pit zips or side zips on pants, helps you dump heat on steep climbs so you don’t soak your layers in sweat. A ski coat would work well for winter hikes, since most are already designed to keep you warm but not overheating.

Winter also turns the smaller pieces of clothing into big deals. Hats, gloves, and neck gaiters aren’t accessories, they’re survival tools. A warm hat keeps heat from escaping your head, while a neck gaiter or balaclava protects your face from cold air and windburn. Gloves are especially important, and many hikers bring two pairs: lighter gloves for moving and thicker, insulated ones for stopping. Mittens can be surprisingly warmer than gloves, and spare gloves are worth their weight in gold if one pair gets wet in snow.

Footwear has to do double duty in winter by providing warmth and traction. Insulated, waterproof boots help keep feet from going numb, and wool socks add warmth while managing moisture. In deep snow or during storms, gaiters help keep snow from sneaking into your boots and melting against your socks. Cold feet can ruin a hike quickly, and in severe cases they can become a safety issue, so winter footwear is not the place to cut corners.

When you’re dressed well, winter mountains feel crisp and energizing instead of harsh and stopping for a break in the snow feels peaceful rather than punishing. The right clothing turns winter hiking from an endurance test into an adventure you actually want to linger in. Across both seasons, one of the most important principles is to avoid cotton, which holds moisture and can quickly make you cold. Mountain hikers should always dress with the assumption that conditions may worsen, not improve. In summer, that means packing layers for cold rain and wind despite warm forecasts, and in winter, it means carrying enough clothing to stay warm if movement stops due to injury, weather, or delays. Dressing appropriately in the mountains isn’t about comfort alone—it’s a key part of staying safe.

Here's the most important rule: Dress for the coldest, wettest, windiest conditions you might encounter, and adjust as you go. It's a whole lot easier to stay warm than it is to get warm.