Getting your layering right is the most important thing you can do to stay comfortable on a backcountry tour. But when you're new to touring, layering can be one of the last things you dial in. You're already learning how to skin, navigate avalanche terrain, and manage a mountain of new gear—so yeah, layering often gets overlooked. Fortunately, we've developed a tried-and-true layering method, refined and tested over more than a decade: the two-jacket system. Two jackets? That’s right—one for the up, one for the down. Whether I'm touring in a full-on winter blizzard or climbing a glacier in the spring sun, I rely on this system. It’s undefeated. Here’s how it works. The Two-Jacket System Layering from the bottom up: Baselayer Up Jack (Optional, depending on conditions) Midlayer Shell jacket On the uphill, wear your baselayer and your Up Jack. That’s it. Throw your shell jacket over the Up Jack when it's time to descend. If you're getting cold during breaks or at the summit, layer a puffy on top. Nothing ever goes between your baselayer and your Up Jack. That’s the core of the system—it’s sweat-wicking, insulating, and weather-blocking—a super system for staying dry, warm, and comfortable in almost any condition. Get Your Baselayer Dialed For the two-jacket system to work, your baselayer has to do its job. I learned this lesson the hard way on my first “real” tour in college, climbing Ski Hayden outside of Aspen. We were hours into the climb, nearing the sun-blasted summit face, and I was slogging up in a soaked cotton T-shirt under a fleece. “Is that cotton?” my buddy Justin asked, incredulously. “Yeah,” I gasped. He just laughed and shook his head. That said it all. I’d heard “cotton kills,” but still wore my favorite tees inbounds and didn’t have many technical layers at the time. I didn’t die, but I was wet and uncomfortable all day. Your baselayer’s job is to remove moisture from your skin and dry quickly. Synthetic fabrics (polyester, nylon, polypropylene) do this fast and efficiently, which is why high-output athletes often prefer them. But Merino wool is king when it comes to comfort, temperature regulation, and versatility. Unless you have an aversion to wool, Merino is our top recommendation for new backcountry skiers and riders. Pair a Merino baselayer with the Up Jack, and you’re set up for layering success. You can also choose different weights or styles of Merino depending on the projected forecast to dial things in even further; go thicker/heavier for the colder days, and lighter/thinner for those days where you know it will be getting warm. The Up Jack: Your Go-To Uphill Jacket As the name suggests, the Up Jack was built for climbing. It’s constructed from a single-layer fabric with an ultralight, breathable windproof coating. That coating is key—it blocks wind and light weather while still letting moisture escape. Not all windbreakers are created equal. Some use a Cire finish—a glossy, heat-treated fabric that’s windproof but traps sweat like a trash bag. (Think: classic K-Way jackets.) The Up Jack, on the other hand, is soft, breathable, and lightweight—barely noticeable while you’re moving but tough enough to hold off wind and light precipitation. It also keeps you shaded and protected from long days under the sun, with the hood acting as a great shield for your neck and ears. The amount of times this layer has saved me from gnarly glacier burns are countless. So how does it differ from other windbreakers? Most ultralight options are optimized for running or hiking. They're lighter and more compact but not built to handle the rigors of winter touring. The Up Jack uses a more durable fabric than your average running wind shell, but it’s still highly packable. Oh, and it’s got the oversized hoodie pocket because we’re pocket enthusiasts at TREW. Use it to warm your hands on the skin track or stash glove liners, snacks, or a buff. Little things like this make a big difference in the backcountry. The Magic of Not Having to Transition The beauty of this system? The Up Jack stays on. When it’s time to descend, just throw your shell on top. When it’s time to climb again, remove your shell, and boom—you’re already in your uphill kit. No fidgeting, no switching layers, no delays. An added bonus on those warmer days is that The Up Jack can hold it's own on the downhill without an added shell on top. When the sun is shining and the temps are spiking, just point 'em downhill and let the Up Jack take you an a ride. Be the Norm, Start Warm (Credit: Graybird Guiding) We all know the rule: be bold start cold. But let’s be real—nobody likes starting a skin while freezing. That’s where a little nuance comes in. You can “start warm” by tossing a midlayer or shell over your Up Jack. Just make sure that whatever layer you shed first isn't underneath the Up Jack. If it’s snowing or precipitating, start your climb with your shell on top of the Up Jack, then delayer when you hit your stride. The key: don’t wait until you're drenched in sweat. Delayer before the sweat starts. That’s how you stay dry, and that’s how the system works best. Final Word Backcountry layering doesn’t need to be complicated. Start with a reliable baselayer, trust the Up Jack on the uphill, and keep your transitions simple with the two-jacket layering system. We’ve tested this in all kinds of conditions, and it just works. Got questions about how to dial your kit? Drop us a line or swing by the shop—we’re always down to talk gear. SHOP OUR GO-TO BACKCOUNTRY LAYERS
