Review: Arc’teryx Atom LT Hoody

Breathable Insulated Jacket
Arc’teryx Atom LT Hoody
$259, 12 oz. (men’s medium)
Sizes: men’s XS-XXXL, women’s XS-XXL

From days of backcountry skiing and winter hikes in my local foothills to biking around town on cold days, the Arc’teryx Atom LT Hoody has spent almost as much time on me as it does in my closet. In a category of breathable insulated jackets designed for being active in cool to cold temps—like backcountry snow sports, hiking, and climbing—the Atom LT Hoody’s weight and features make it uniquely versatile for a wide range of activities and users.

On a morning when the trailhead temp sat at 20° F as a friend and I set out for a half-day of backcountry skiing, I pulled the hood up and this puffy kept me warm over two light base layers while skinning uphill in cold shade. But even more impressively, once my body was churning out heat, the wide, stretch side and underarm panels dumped that heat and moisture so well that I didn’t have to take it off until we entered direct sunshine near the top of our ascent.

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The Arc’teryx Atom LT Hoody.
The Arc’teryx Atom LT Hoody.

The Coreloft Compact synthetic insulation delivered all the warmth I needed while standing in a snow pit evaluating avalanche hazard. It also lost none of its insulative properties when I did build up some moisture inside while skiing downhill in warm sunshine. In fact, I was surprised to notice that it was damp at all at the end of a day of skiing, because I hadn’t felt any cooling effects from that wetness. Wearing it as an outer layer on the downhill conclusion of another ski tour under overcast skies, with the temp just below freezing and a light snow falling, I remained perfectly warm.

The close-fitting, insulated StormHood, adjustable with a single drawcord in the back, boosts warmth significantly and fits under a helmet. The athletic fit—in an unusual six women’s sizes and seven men’s sizes—leaves space for a couple of warm base layers and allows excellent freedom to move, enhanced by stretch throughout, but especially by the huge stretch in the side panels. Design details right down to the adjustable hem, sleeve length, and low-profile, stretch cuffs—which pull over light gloves or mittens or fit easily underneath the gauntlet of heavier handwear—make this hoody supremely comfortable to wear and slip on or off.

The tough, water-resistant, breathable Tyono 20 shell fabric blocks wind well and shed steadily falling snow when I ski toured without a shell over it. Bonus green cred: The color is added at the polymer level, which Arc’teryx reports saves water, reduces CO2 emissions, and increases fabric colourfastness.

At 12 ounces, the midweight Atom LT Hoody is very packable, compressing about as well as a 700-fill down jacket of the same weight. The two zippered hand pockets are each roomy enough for one big ski glove or mitten and the one zippered inside pocket is more than large enough for a smartphone.

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The Arc’teryx Atom LT Hoody.
The Arc’teryx Atom LT Hoody.

The Verdict

An incredibly versatile insulation piece that functions as an outer or middle layer, with good warmth for its weight and impressive breathability, the Arc’teryx Atom LT readily rises to as many uses as you can conceive, from hiking, backcountry skiing, and climbing to bike commuting and serving as a campsite puffy in temps down to around 40° F in summer in the mountains.

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See my other reviews of breathable insulated jackets, my picks for “The 10 Best Down Jackets,” and all of my reviews of outdoor apparel that I like.

NOTE: I tested gear for Backpacker Magazine for 20 years. At The Big Outside, I review only what I consider the best outdoor gear and apparel. See my Gear Reviews page at The Big Outside for categorized menus of all of my reviews and my expert buying tips.

—Michael Lanza

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