Reviewer Info: 5’3”, 120 lbs.
Size Tested: Small
Color: Azulene (Purple)
- Moisture resistant Luminara (20D nylon Ripstop) outer fabric with DWR finish
- Breathable, stretchy Polartec® Power Stretch® Side Panels
- Insulated Hood
- Full front zip with wind flap
- Stretch-knit sleeve cuffs
- Drop back, laminated and adjustable hem
- Weight: (12.9 oz for size Medium, 366 grams)
- Insulation: 60 grams of Coreloft insulation
Days Skied: 30+
Days Worn: 60+
The Arc’teryx Atom LT is a lightweight, synthetic, insulated jacket designed to provide warmth without excessive bulk or weight. Arc’teyrx designed this jacket for outdoor enthusiasts of all kinds, and it lends versatility in situations where a fleece or down jacket might not be your best option.
The Atom LT is designed to be close fitting with an athletic cut so it can easily be layered underneath a jacket or shell. The Coreloft insulation is incredibly thin, and many people are surprised when they feel how thin the jacket is.
Overall, I would say that this jacket has a very flattering fit. It flares out slightly at the hemline, giving it a nice feminine shape. This is augmented by the breathable stretch panels on each side, which provide a bit of structure so the jacket doesn’t hang loosely on the body.
There are two toggles located on either side of the hemline to loosen or tighten the hem as needed. The drop hemline on the back neatly covers a good portion of the backside for added coverage.
I chose a size small, and it fits perfectly when worn over a baselayer (I am 5’3” and 120 pounds). If you intend to wear this jacket atop several layers, I may suggest sizing up because it is rather close fitting. I typically choose a size small for most Arc’teryx products, and this jacket fit as expected. (I tried on a size XS, and found it too restricting.) For reference, I also wear a size small in most brands, such as The North Face, Marmot, and Patagonia.
The sleeve length on this jacket is fairly standard, which I found to be perfect—not too short, not too long. The sleeves also feature neat asymmetric elastic cuffs that can easily fit under gloves to lock out wind.
When skiing, I typically wear this jacket as an insulating thermal layer underneath my waterproof / breathable ski shell. However, because it does provide some water resistance, I also use it as a stand-alone piece on milder days (high 30s to 40s Fahrenheit) when knocking out errands around town, hiking, or running. I’ve also worn it when skinning in the backcountry when I need a little warmth but didn’t want to sacrifice breathability. It’s a great option for athletic endeavors because, in my experience, it fits closely but does not impede movement.
This jacket is highly water resistant though not waterproof. When faced with rain or light snow, water droplets bead right up on the jacket surface and do not easily penetrate the fabric. What I found most impressive was how quickly this jacket dries. When I did get it damp in light rain, it was only a matter of 10 minutes or so before the jacket felt dry to the touch. The Atom LT wouldn’t fare well in an outright downpour, but I found it to be more than adequate in light precipitation.
Because the Atom LT is designed with layering in mind, the zippers aren’t water resistant, nor are the seams sealed.
In terms of breathability, this jacket is strategically designed for athletic endeavors. The two stretchy Polartec® panels on either side of the jacket span about 5 inches in width and run from beneath the armpit to the hemline. They are thinner than the rest of the jacket and backed with a very fine microfleece fabric. These panels provide a huge breathable area for moisture and water vapor to escape, meaning this jacket is excellent for aerobic activity. This is one of the reasons I think it makes a stellar option for backcountry tours. As an added bonus, the thinness of the CoreLoft insulation also means that the jacket in its entirety is fairly breathable.