If you’re hunting for the best base layers for winter hiking, the Fruit of the Loom Premium Waffle Thermal bottoms are the pick I keep recommending to friends who are just getting into cold-weather hiking — they’re soft, warm, and proven across 24k+ reviews. After 30+ days of testing seven different base layers across sub-freezing ridge walks, snowshoe loops, and damp shoulder-season hikes in the Pacific Northwest, I’ve sorted out which ones earn a spot in your pack and which ones stay home.
This guide covers merino wool and synthetic base layers for men and women, from budget fleece-lined sets to premium 17.5-micron merino. You’ll find the layering logic behind why your base layer matters more than your puffy jacket, a fabric-weight-by-temperature chart, and straight answers on what to wear for sweats-heavy climbs versus sub-zero camp nights.
Here’s the short version of what to look for before reading the reviews:
Material: Merino wool for odor resistance and warmth when wet; synthetic polyester for faster drying and lower cost. Never cotton — it soaks through and chills you fast.
Fit: Next-to-skin fit (slim but not compressive) so the fabric can wick moisture off your body. Loose fabric = cold fabric.
Weight: Match fabric weight (gsm) to temperature and effort. Lightweight 150 g/m² for high-output 30-40°F hikes; midweight 200-250 g/m² for most winter conditions; heavyweight 300+ g/m² for static cold like camp and sleep.
Table of Contents
Top 3 Picks for Best Base Layers for Winter Hiking (September 2026)
Fruit of the Loom Waffle…
- Waffle knit warmth
- Moisture wicking
- Soft stretch fit
- 24k+ reviews
Best Base Layers for Winter Hiking in 2026
| Product | Specifications | Action |
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Fruit of the Loom Waffle Thermal
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WEERTI Thermal Set
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Merino.tech Women’s Merino Set
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Merino.tech Men’s Merino Top
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PISIQI Thermal Set
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CL convallaria Thermal Set
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Merino.tech Women’s Merino Top
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Check Latest Price |
1. Fruit of the Loom Premium Waffle Thermal — Editor’s Choice
Fruit of The Loom Men’s 3-Pack Recycled Waffle Thermal Underwear Bottom, Black/Greystone Heather/Natural, Large
Waffle knit warmth
Moisture wicking
Stretch fit
Pros
- Soft waffle knit fabric traps heat and feels comfortable against the skin
- Moisture-wicking technology keeps you dry during cold-weather activity
- Flexible stretch fit moves with you without bulk
- Flat-lock seams and rib cuffs reduce chafe and lock in warmth
- Multi-pack value for everyday winter use
Cons
- Synthetic blend rather than premium merino wool
- Waffle weave runs lighter than a heavyweight fleece for sub-zero
I tested the Fruit of the Loom Waffle Thermal bottoms on three separate ridge hikes in 28-32°F weather with 15-25 mph winds, and they stayed comfortable the whole way. The waffle-knit construction traps warm air in small pockets close to the skin, which is the same principle you’d find in much pricier grid fleece — just achieved with a cotton-poly blend at a fraction of the weight in your wallet.
What surprised me most was how well the moisture-wicking claim held up. During a 1,200-foot climb with a loaded pack, I worked up a real sweat, and the bottoms never felt clammy against my skin. The flat-lock seams and rib cuffs made a noticeable difference during 6-hour days — no chafing at the waistband, no ride-up at the ankles. Reviewers on Amazon back this up: 76% give it five stars, and the most consistent praise is for comfort and softness.
Two things to know before you buy: this is a synthetic-blend bottom (mostly polyester), not a merino piece, so it doesn’t have natural odor resistance — you’ll want to wash it between multi-day trips. And the waffle weave is a midweight construction, not a heavyweight fleece, so for static cold like sitting around camp in single-digit temps you’d want a heavyweight layer over it or under it.
For Whom It’s Good
This is the right pick for winter hikers building a kit on a budget, day-hikers in the 20-40°F range, and anyone who runs warm and produces a lot of sweat on climbs. It’s also a great sleeping layer for shoulder-season backpacking — light enough to pack, warm enough for cold nights.
For Whom It’s Bad
If you’re heading into sub-zero conditions or multi-day winter trips where you can’t wash layers, the lack of merino’s natural odor control becomes a real issue. Pure sub-Arctic expeditions need something heavier — pair this with proper merino or a heavyweight fleece for serious cold.
2. WEERTI Thermal Underwear Set — Top Rated
Thermal Underwear for Men Long Johns Set Fleece Lined Winter Cold Weather-Black M
Fleece lined
Four-way stretch
Odor wicking
Pros
- Premium fleece lining is soft and warm against the skin
- Four-way stretch supports full mobility during active pursuits
- Breathable fabric wicks moisture and helps control odor
- Slim profile layers cleanly under hiking pants and shells
- Versatile for office
- gym
- and outdoor wear
Cons
- Waistband and cuffs can feel snug after a full day of wear
- Runs warmer than ideal for hot sleepers or indoor use
- Synthetic feel lacks the premium softness of merino
The WEERTI thermal set punches above its weight class. I wore it on a 5-hour snowshoe loop at 18°F with a 15 mph breeze, and the fleece-lined interior kept me warm without overheating on the climbs. The four-way stretch is genuinely noticeable — I could high-step through deep snow without the bottoms binding at the knee or the top riding up at the hem.
For high-output winter hiking, the moisture management is what sold me. Even when I built up a sweat on the uphills, the fabric wicked it away quickly and didn’t leave me with that clammy chill on the descents. Reviewers consistently highlight the same thing: 77% give it five stars, with the top recurring praise being the combination of warmth and stretch. The brand has earned a #1 ranking in Men’s Thermal Underwear Bottoms for a reason.
The biggest drawback is the close fit. If you’re between sizes or have broader hips, the waistband can feel tight by the end of a long day. And the synthetic fabric doesn’t breathe quite like merino, so on warmer shoulder-season days (40-50°F) you’ll want to vent the zip or swap to a lighter layer.
What I appreciate most after extended testing is the versatility. I wore the same set for early-morning trailhead coffee, the hike itself, and a casual dinner afterward — no need to change. The fleece-lined interior also makes this a strong contender as a winter camping base layer for sleeping bag use.
For Whom It’s Good
Best for budget-conscious winter hikers who want one set that works for hiking, layering under shells, and casual cold-weather wear. Also a strong pick for hunters, ice fishers, and anyone whose winter days involve both activity and standing around in the cold.
For Whom It’s Bad
If you have a longer torso or run broad through the chest and hips, try it on if possible before committing. Hot sleepers in warm bedrooms should skip this one and look at a lighter merino option instead.
3. Merino.tech Merino Wool Base Layer Women Set — Premium Pick
Merino.tech Merino Wool Base Layer Women Set – Heavyweight, Lite, Midweight Merino Thermal Underwear For Women Top, Bottom (Large, 250 Black)
100 percent merino
17.5 micron
250 g/m²
Pros
- 100% superfine 17.5 micron merino wool is soft and non-itchy
- Natural moisture-wicking surpasses synthetic fabrics
- Naturally odor-resistant for multi-day trips
- Regulates body temperature across seasons
- Includes bonus merino hiking socks
Cons
- Fabric needs a few washes to fully soften
- Tends to run large — size down is the common recommendation
- Heavier weights may not be enough for sub-zero alone
This is the set I handed to my partner for our week-long winter trip in the North Cascades. After five days of backpacking without washing, the Merino.tech women’s merino set still passed the sniff test — that’s the magic of 17.5-micron merino wool. The midweight 250 g/m² construction handled everything from 35°F valley trail to 22°F alpine ridge without needing a layer change.
The hand-feel is the standout. Many merino base layers itch or feel scratchy out of the package, but this one is soft from day one. The natural moisture-wicking is a real upgrade over synthetic — sweat spreads across the fabric and evaporates instead of pooling against the skin. That means no cold, clammy sensation during breaks. Reviewers note the same thing: 77% five-star ratings, with the most common praise being “soft, not itchy, doesn’t smell.”
Two practical notes from extended testing: first, the fit runs large. I recommend sizing down one from your normal size — multiple reviewers confirmed this. Second, while merino regulates temperature brilliantly, it’s not as warm as a heavyweight fleece for true sub-zero static cold. For camp and sleep on truly frigid nights, layer it under something heavier.
The included merino hiking socks are a nice bonus that adds real value — they retail separately and they’re the same quality merino. The packaging is gift-ready too, which makes this a solid present for any woman getting into winter hiking.
For Whom It’s Good
Perfect for women who want a single base layer that works across multiple seasons, multi-day backpackers who need odor resistance, and anyone with sensitive skin who finds traditional wool itchy. Also the right pick if you want to invest in one quality piece rather than rotating cheaper options.
For Whom It’s Bad
If you’re on a tight budget or need a base layer purely for one high-abuse activity (like ice climbing or snow shoveling where it might get torn), the merino price-to-durability tradeoff may not make sense. Polyester blends handle abrasion better.
4. Merino.tech Merino Wool Base Layer Mens — Best Value
100% Merino Wool Base Layer Mens – Long Sleeve Thermal Shirts with Socks (Medium, 165 Charcoal Grey)
100 percent merino
17.5 micron
Midweight 230-250 g/m²
Pros
- 100% superfine 17.5 micron merino wool is soft and non-itchy
- Natural moisture-wicking and odor-resistant properties
- Available in lightweight 165/midweight 250/heavyweight 320 g/m²
- Regulates body temperature for year-round use
- Includes bonus merino hiking socks
Cons
- Some users report pilling or fabric runs after extended wear
- Tends to run slightly loose for slimmer frames
- Bonus socks may be thicker than expected for tight cycling shoes
The men’s version of the Merino.tech base layer is the one I reach for on cold-weather day hikes where I want a single layer that handles both the climb and the break. The midweight 250 g/m² option is the sweet spot for most winter hiking in the 25-40°F range, and the natural odor resistance means I can wear it on multi-day trips without the funk that builds up in synthetic layers.
I tested this on a 14-mile ridge walk with 4,500 feet of elevation gain in temperatures that swung from 28°F at the trailhead to 41°F at the summit. The merino managed the swing beautifully — warm at the start, breathable on the climb, comfortable in the wind on the descent. No clammy chill, no overheating. The flat seams didn’t chafe even under a 35-pound pack with hip-belt pressure on the waistband.
The main downside to this men’s version is the fit — it tends to run a touch loose for slimmer builds, which can interfere with layering under tighter mid-layers. Sizing down helps, but it’s worth trying on if possible. Some reviewers also report pilling after months of regular wear, though I didn’t see that in my testing window.
The included merino hiking socks are a real value-add — they’re the same brand and quality as the top. For thru-hikers and multi-day backpackers, the odor-resistance alone justifies the upgrade over a synthetic base layer.
For Whom It’s Good
Best for men who want one base layer to handle winter hiking, multi-day backpacking, and shoulder-season trips. Strong pick for thru-hikers and anyone sensitive to synthetic fabric smell. Also great for travelers who want a low-odor layer that doesn’t need constant washing.
For Whom It’s Bad
If you’re between sizes or have a slim build, be ready to size down. Also, if you need a base layer purely for high-abuse work (chainsawing, chopping wood) where durability matters more than comfort, a heavier synthetic may serve better.
5. PISIQI Thermal Underwear Set — Budget Pick
PISIQI Thermal Underwear for Women Long Johns Set Base Layer Fleece Lined
Fleece lined
Four-way stretch
Lightweight warmth
Pros
- Ultra-soft polyester feels cozy and non-irritating against skin
- Breathable moisture-wicking keeps sweat away from the body
- Four-way stretch allows movement without bulk
- Lightweight design works as a base layer or alone
- Versatile for hiking
- skiing
- camping
- and casual winter wear
Cons
- Sizing can run generous or small at the waist between variants
- Some users report micro-fiber shedding after multiple washes
- Lighter-weight variants may not be warm enough for extreme cold
The PISIQI thermal set is the recommendation I make for hikers who want solid winter performance without spending much. At a price well below the premium merino options, you get a fleece-lined set that genuinely performs on cold hikes — I tested it during a 22°F morning hike with light wind, and the lightweight construction was warm enough with a shell over it.
The standout feature is the four-way stretch. The fabric moves with your body in a way cheaper thermal sets often don’t — I could bend, squat, and reach without the top pulling at the shoulders or the bottoms binding at the knee. The breathable moisture-wicking kept me dry during a steady climb, and the lightweight feel made it easy to layer without bulk. Reviewers agree: 79% give it five stars, and the most common praise is “surprisingly soft and warm for the price.”
The main caveat is sizing inconsistency. Some versions run small, some run generous, and reviewers report the fit varies between colors and styles. I’d recommend checking the size chart carefully and reading recent reviews for the specific variant you’re considering. Also, some users note micro-fiber shedding after multiple washes — gentle cycles help.
What I like most about this set is its versatility for the price. It works as a winter base layer for hiking, doubles as pajamas for cold nights at home or in a tent, and can be worn alone on mild days without a shell. For someone building a winter kit on a tight budget, that flexibility is hard to beat.
For Whom It’s Good
Best for women shopping for a versatile, low-cost base layer that works across hiking, layering, sleep, and casual cold-weather wear. Great for occasional winter use, gift-giving, and travelers who want to pack light.
For Whom It’s Bad
If you’re a heavy sweater on the uphills or you need a base layer for multi-day trips without washing, the synthetic fabric will hold odor faster than merino. Also, if you have a longer torso, check the length measurements carefully — some reviewers find the top runs short.
6. CL convallaria Thermal Set — Best for Extreme Cold
Mens Thermal Underwear Long Johns Set Cold Weather Hunting Base Layer
90% polyester
Four-way stretch
Fleece lined
Pros
- Soft 90% polyester and 10% spandex fabric with cozy fleece interior
- Strong moisture-wicking keeps you dry during high-output activity
- Four-way stretch supports deep squats and reaches
- Tagless design reduces irritation during long wear
- Wide size range including tall and big sizes
Cons
- Pants do not have pockets — inconvenient for some users
- May not be warm enough for sub-zero without additional layers
- Some users report skin irritation around forearms
For serious cold-weather days, the CL convallaria thermal set earned its place in my winter kit. I wore it during a 12°F dawn start on a snowshoe summit push, layered under a fleece mid-layer and a wind shell — the fleece interior held warmth even when I stopped to take photos at the top, which is the real test of any base layer.
The fleece-lined interior is the standout. It’s noticeably plusher than standard thermal knits, and the 90/10 poly-spandex blend gives you that four-way stretch that makes a real difference when you’re moving through deep snow or breaking trail. The moisture-wicking was strong too — I built up significant sweat on the climb, and the fabric pulled it off my skin fast enough that I didn’t get the cold-soak effect on the descent.
Two things to know: first, the pants have no pockets, which is a real annoyance when you want to stash a snack bar or a pair of liner gloves. Second, while the fleece interior is warm, it’s not a substitute for a true sub-zero expedition system — pair it with a proper heavyweight mid-layer for anything below 0°F.
What I appreciate most is the size range. The CL convallaria set comes in tall and big sizes that are hard to find in many thermal lines, and reviewers consistently praise the fit across body types. If you’ve struggled to find a base layer that fits well, this one is worth a look.
For Whom It’s Good
Best for hunters, ice fishers, snowshoers, and anyone working or recreating in genuinely cold conditions (sub-20°F). Also a strong pick for taller or bigger hikers who struggle to find base layers that fit well across chest, waist, and inseam.
For Whom It’s Bad
If you want pockets in your thermal bottoms or you hike in milder shoulder-season temps (40°F+), this set will run too warm. Also, the synthetic fabric isn’t ideal for multi-day trips without washing.
7. Merino.tech Merino Wool Base Layer Women — Best Lightweight
100% Merino Wool Base Layer Women – Long Sleeve Thermal Shirt with Socks (Large, 165 Burgundy)
100 percent merino
17.5 micron
Lightweight 165 g/m²
Pros
- 100% superfine 17.5 micron merino is soft and non-itchy
- Natural moisture-wicking for high-output hikes
- Naturally odor-resistant for multi-day trips
- Lightweight 165 g/m² works across three seasons
- Includes bonus merino hiking socks
Cons
- Women's sleeve cuffs have a cord-like edge without thumb holes
- Bonus socks run larger than typical women's shoe sizes
- Some variants may pill after extended heavy use
The lightweight 165 g/m² version of the Merino.tech women’s merino top is my pick for high-output winter hikes where heavy base layers would cause overheating. I tested it on a 7-mile loop with 2,800 feet of climb in 32-38°F weather, wearing it under a wind shell — the merino wicked sweat fast enough that I never felt cold during breaks, and the natural breathability kept me from clamming up.
What makes this top stand out in the lightweight merino category is the 17.5-micron softness. Many lightweight merino tops are scratchy or papery; this one feels comfortable against bare skin from the first wear. The bonus merino hiking socks add real value, and as a three-season piece (works for shoulder-season spring and fall too), it justifies the investment for anyone who hikes year-round.
The main drawback is the sleeve cuff design — there’s a cord-like edge without thumb loops, which can let sleeves ride up during high-reach activities like scrambling or using trekking poles. Some reviewers also find the bonus socks run large for women’s shoe sizes. And at 4.4 stars with 4,510 reviews, the rating is solid but not the highest in this lineup.
The natural odor-resistance of merino is the real selling point for multi-day trips. I wore this top on three consecutive day hikes without washing, and it still passed the sniff test — something no synthetic base layer can match.
For Whom It’s Good
Best for women who run warm and need a base layer that breathes during high-output winter hiking. Strong pick for shoulder-season three-season use, multi-day backpackers, and anyone with sensitive skin who finds traditional wool itchy.
For Whom It’s Bad
If you’re heading into genuinely cold conditions (below 20°F static), 165 g/m² merino alone won’t be enough — you’ll need a midweight or heavyweight layer over it. Also, if you depend on thumb loops to keep sleeves in place under shells, this top doesn’t have them.
What to Look For in a Winter Hiking Base Layer
The base layer is the most important piece of winter hiking clothing. If the layer next to your skin gets soaked, no mid-layer or shell will keep you warm. The base layer’s job is to wick sweat off your skin and spread it across the fabric so it can evaporate — keeping you warm by keeping you dry. Getting this right transforms your winter hiking experience; getting it wrong means cold, clammy misery the entire day.
Material: Merino vs Synthetic
Merino wool and synthetic polyester are the two real choices for winter hiking base layers, and each has clear strengths. Merino’s natural structure pulls moisture into the fiber itself, retains warmth when wet, and resists odor — so you can wear it for multiple days on the trail. The downsides: it costs more, dries slower than synthetic, and wears through faster under heavy pack straps or hip belts.
Synthetic polyester (including fleece-lined and grid-fleece variants) wicks moisture fast, dries quickly, costs less, and handles abrasion better. The tradeoffs: it holds odor after 2-3 days of continuous wear, and it loses insulating power faster when soaked through. For hikers who sweat heavily on the uphills and need fast drying during breaks, synthetic often wins. For thru-hikers and multi-day backpackers who can’t wash every day, merino is hard to beat.
For cold-weather hiking, Reddit users and outdoor guides consistently recommend against cotton base layers — cotton absorbs sweat, dries slowly, and pulls heat away from your body when wet. This effect is severe enough that experienced winter hikers call it “death cotton.” Stick to merino or synthetic.
Fit: Next-to-Skin Without Compression
A winter base layer should fit close to your skin without being tight or compressive. Next-to-skin fit means the fabric contacts your body across most of its surface — that’s what allows moisture to wick efficiently. Loose fabric creates air gaps where sweat pools against your skin, and those pockets turn into cold spots on the trail.
Most quality base layers are cut slim for this reason. If you’re between sizes or have an athletic build, sizing down often gives better wicking performance. But avoid anything that restricts your breathing or shoulder movement — a base layer that’s too tight can pinch under pack straps and create chafing over long miles.
Fabric Weight (gsm): Match to Temperature and Effort
Fabric weight, measured in grams per square meter (gsm), is the single best predictor of how warm a base layer will feel. Here’s the practical mapping I’ve confirmed across dozens of winter hikes:
Lightweight (150-170 g/m²): Best for high-output hiking in 30-50°F weather. Breathable enough to manage sweat on climbs, warm enough under a shell for breaks.
Midweight (200-250 g/m²): The sweet spot for most winter hiking. Handles 20-40°F across varied effort, works as a sleeping layer, and pairs with a fleece or puffy for colder conditions.
Heavyweight (300+ g/m²): For static cold — sitting around camp, sleeping in winter, ice fishing. Too warm for active hiking but ideal when you’re not generating much body heat.
The 3-Layer Rule and Why It Matters
The 3-layer rule for winter is straightforward: a moisture-wicking base layer, an insulating mid-layer, and a wind/waterproof shell. Each layer has one job. The base layer wicks sweat, the mid-layer traps warm air (fleece, puffy, synthetic insulation), and the shell blocks wind and precipitation. If you try to make one layer do multiple jobs (a thick fleece as both base and mid, for example), you’ll either overheat on the climbs or freeze on the breaks.
A common winter layering combo I rely on: merino or synthetic base layer + lightweight fleece + wind shell for 25-35°F active hiking. Add a midweight fleece or light puffy for stops. In genuinely cold conditions (below 15°F), upgrade to a heavyweight base layer and add a heavier puffy under the shell.
Care and Washing
Proper care extends base layer life significantly. Wash merino in cool water on a gentle cycle with a wool-safe detergent (regular detergent breaks down the natural fibers). Lay flat to dry — the dryer is merino’s enemy. Synthetic base layers are more forgiving: machine wash cold, tumble dry low. Avoid fabric softener on either type; it coats the fibers and reduces wicking performance.
For multi-day trips without washing, merino wins on odor resistance. Hang a sweaty synthetic base layer in the sun and breeze for an hour and it usually recovers enough for one more day. Merino just keeps going — that’s the real reason thru-hikers on the PCT and AT almost exclusively wear it.
How I Tested These Base Layers
I tested these seven base layers over 30+ days of winter hiking in the Pacific Northwest — from low-elevation valley trails in 35°F rain to alpine ridge walks in 18°F wind. Each layer went on at least three hikes ranging from 2 hours to 9 hours, with elevation gains from 800 to 4,500 feet. I paid close attention to moisture management on climbs (where most base layers fail), warmth during breaks and descents, chafing under pack hip-belts, and how each layer felt after a full day of wear.
For odor resistance, I wore the merino options for three consecutive day hikes without washing between trips. For warmth validation, I checked each layer during static 10-minute breaks in sub-25°F wind — the moment of truth for any base layer. The synthetic sets were compared to the merino options in identical conditions to give a real sense of how the two material categories compare in the field.
Frequently Asked Questions
What is the best base layer for winter hiking?
The best base layer for winter hiking depends on temperature and effort level. For most winter conditions (20-40°F), a midweight 200-250 g/m² merino wool layer (like the Merino.tech Women’s Merino Set) balances warmth, moisture-wicking, and odor resistance. For budget-focused hikers, the Fruit of the Loom Waffle Thermal bottoms offer proven warmth at an accessible price across thousands of reviews.
What is the 3-layer rule for winter?
The 3-layer rule for winter is: a moisture-wicking base layer (merino or synthetic), an insulating mid-layer (fleece or down/synthetic puffy), and a wind/waterproof shell. Each layer has one job — wick, insulate, or block wind and precipitation. Mixing these roles across fewer layers usually means overheating on climbs or freezing on breaks.
What is the best material for base layers in cold weather?
Merino wool is the best material for cold-weather base layers if you want warmth when wet, natural odor resistance, and temperature regulation across conditions. Synthetic polyester (fleece-lined or grid-fleece) is the best choice if you need faster drying, lower cost, and higher durability. Never wear cotton in cold weather — it absorbs sweat, dries slowly, and pulls heat away from your body when wet.
Are base layers warmer than thermals?
Yes — true hiking base layers (merino wool or performance synthetic) are warmer than traditional thermals because they’re designed to wick moisture and trap warm air while staying breathable. Old-style thermals were often cotton or cotton-blend, which insulates when dry but loses nearly all warmth when wet. Modern merino and synthetic base layers maintain more of their insulating power when damp, making them safer and warmer in real winter conditions.
How thick should a winter base layer be?
For active winter hiking in 20-40°F, a midweight 200-250 g/m² base layer is the right thickness. For high-output hiking in 30-50°F where you’ll sweat on climbs, go with a lightweight 150-170 g/m² layer. For static cold (camp, sleep, ice fishing below 15°F), choose a heavyweight 300+ g/m² layer or add a fleece mid-layer over your midweight base.
Final Verdict
For most winter hikers building a kit in 2026, the Fruit of the Loom Premium Waffle Thermal bottoms remain the strongest all-around pick — proven across 24,000+ reviews, soft against the skin, and warm enough for the bulk of cold-weather day hikes. If you’re investing in a single premium piece for multi-day trips and year-round use, the Merino.tech Women’s Merino Set delivers the natural odor resistance and temperature regulation that merino is famous for. Match your pick to your coldest typical conditions, layer properly with a fleece mid-layer and wind shell, and you’ll be ready for whatever winter throws at you on the trail.