Free 2-Day Shipping on Orders Over $50* – Limited Time Only

Let the lightweight Arc'teryx Men's Alpha LT Jacket protect you from wet weather on your alpine ascent. Using an ever-reliable Gore-Tex Pro membrane and WaterTight external zippers, this jacket boasts guaranteed waterproof and breathable protection to get you up that mountain comfortably. Arc'teryx improved its StormHood to fit climbing helmets better, and the HemLock system features removable inserts to prevent the jacket from slipping out underneath your harness.

Arc'teryx's athletic fit uses complex e3D patterns with anatomical shaping and gussets to reduce bulk and improve your mobility on the mountain. Zip down the underarm vents while you climb to let out some steam, and zip them back up while you belay your buddy on those cold ledges. The cuffs have laminated hook-and-loop tabs that won't catch or tear off during your ascent.

  • 3-layer Gore-Tex Pro membrane, fully taped seams
  • Athletic fit with e3D, hip length
  • Gusseted underarms
  • Underarm zippers
  • Helmet-compatible StormHood
  • WaterTight external zippers
  • Hem drawcord with HemLock removable inserts
  • Laminated hood-and-loop tabs
  • Reviews
  • Q & A

What do you think about this product?

Have questions about this product?

Excellent Harsh Weather Jacket

  • Familiarity:I've put it through the wringer
  • Fit:True to size

Okay, so here goes. Two yaks and a trekker walk into a bar...I know this is supposed to be about the Alpha Lt., but I couldn't resist and the trekker was wearing an Alpha Lt. jacket. Anyway this is a great jacket and I don't see it listed on the Arcteryx website anymore. Just as the Atom SV 100 gram insulated mid-layer jacket it seems as if Alpha Lt. is being phased out.

Next to it's big brother the Alpha SV, the Lt is four ounces lighter with a very durable face fabric laminated to 3 layers of Gortex. I actually prefer this jacket if I'm expending a lot of energy because of the weight. It also breathes a bit more than the SV although both have great pit zips. The Alpha Lt. has a storm hood like the Alpha SV. It's a little different than the the storm hood on the SV but the cut is the same. I once wrote that the Alpha SV is "finest technical shell ever made." The Alpha Lt is the second finest technical shell ever made. Buy it if you can. You won't be disappointed!

Comparing Alpha and Theta

  • Familiarity:I've used it once or twice and have initial impressions
  • Fit:True to size

I recently ordered three Arc’teryk shells trying to get exactly what I wanted (with plans to return two of them): Alpha SV, Alpha LT, and Theta AR. I tried them on with my climbing helmet, alpine harness, and a down hoody liner, and here are my thoughts on Alpha versus Theta, and SV, LT and AR.

-Alpha has a great overhead reach and the hood fit my helmet quite well, though the hood hung limply when not over my head. The main Alpha design issue is that the only exterior pockets are a pair on your chest near the zipper, which you have to reach over to use (i.e. you use your right hand to reach into the pocket on your left side). This leaves nowhere to put your hands, ever. As for SV vs. LT: the main difference is LT used 2 layer 40D GoreTex, SV used 3 layer 80D. The result is that the SV feels a lot more durable. It’s probably worth the extra 100 dollars if you’re planning to rough it, and it’s only another ½ pound of weight. The other two differences I noticed is that the SV adds a waste cinch six inches from the bottom and a bicep pocket.

-As noted elsewhere, the Theta looks a bit long, though that does add some waterproofing below the waist. The “AR” means it uses 40D GoreTex in most of the jacket, but 80D GoreTex in the forearms, shoulders, upper back, and lower back. I find this to be an optimal tradeoff in terms of weight, durability, and cost. The jacket also has a different neck/hood layout that looks more natural when wore down and still adjusted okay on the helmet. The pockets are set wide on the chest making them a comfortable place to put your hands.

Conclusion: keeping the Theta AR because it uses the right mix of materials and has the right pockets/hood for wearing on the mountain and around town. If you don’t love the length, get the Alpha AR.

-Regarding fit. I’m 6-0 and skinny; medium was fine.

Knocking down a star because of discomfort, a little flimsy for this price.

I don't think this was worth the price

  • Familiarity:I've put it through the wringer
  • Fit:True to size

The fit is a bit strange, very baggy and short, but may work for you depending on your build and preferences. The seam glue will deteriorate and come apart over time.


  • Familiarity:I've used it once or twice and have initial impressions
  • Fit:True to size

Bought this as my new splitboarding and mountaineering shell. Went one size up from my normal (small), to fit over a bunch of layers. For use without layers it will be a little loose, but not too bad. Right after I purchased this I got sick so I haven't had a chance to test it in the field but I thought I would throw a photo up to show fit. Weight and construction on this garment is insane! Arcteryx is worth the price tag for sure. Easily the nicest piece of gear I own in terms of quality. The stitching and taping of this product is the best i've seen. In the picture I have a Patagonia micro puff hoodie on size small. The medium shell fits well without compressing the insulation, and I could easily wear both hoods and a helmet on a cold belay ledge. Nice dropped length in back. Stoked!


Worth It

  • Familiarity:I've used it several times
  • Fit:True to size

I bought this along with the Gamma MX soft shell and am extremely impressed. Not only was this the lightest hardshell I've ever owned but it fits like a glove over the Gamma and is rugged enough not to worry about it when scrambling over rough Wasatch granite. It comes packed with all the features any die hard alpinist would want yet maintains a nice, sleek package any minimalist can appreciate. I was a little unsure of the fit when I first ordered it but was thoroughly satisfied once I put it on. The extra gussets allow the jacket to maintain hip level while raising both arms fully extended which makes this bad boy all that much nicer on long ice climbs. This was my first Arcteryx jacket and it definitely won't be my last! Def worth the price you pay for it! I'd highly recommend this for any serious alpine climber, mountaineer, ice climber, or any outdoors enthusiast for that matter!!!

Winter Armour For Serious Mountain Ops

  • Familiarity:I've put it through the wringer
  • Fit:True to size

When you first take a look at it, you wonder why a jacket so lightweight costs $$$. Then you put it on and you appreciate the athletic fit, the durable construction, the micro seams with micro taping, and the waterproof zippers. Then you wear it during a snowmaggedon event and it all makes sense. The 40D Nylon and Gore-Tex Pro 3L material works like magic. Its deceptively light, but impressively durable, totally waterproof, and still allows your body to breath during high output activity. Unparralleled quality of construction. As a technical shell, the expedition fit has a waistline that is lower at the back than at the front, for compatibility with a harness. That might look goofy for the casual wearer. It also doesn't have hand pockets because you can't use them in a harness anyway. When fully zipped the jacket has a high collar, also an expedition feature. Again, might look goofy. Or you might look like a rugged an of action. That is on you. The hood is adjustable and happiest when you're wearing a climbing helmet. The chest pockets are a good size. Sleeves are a little long so they don't slide up when swinging an axe or placing a cam. Gents, keep in mind that this is purpose built expedition wear. Highly packable, there is no excuse not to bring this with you no matter the time of year. In winter, wear it over layers as a technical shell. In spring/fall wear it over long sleeves to block wind and rain. In summer, wear it over t-shirt for waterproof comfort. However, if price is a major concern there are other jackets with similar features for less $$. 4 stars only for price.


  • Familiarity:I've used it once or twice and have initial impressions
  • Fit:Runs large

I wanted a lightweight rainshell that didn't feel like it was so thin that it would tear if it snagged on a branch. This thing is super light, but it feels like a suit of armor. I love it.

Goal is to mountaineer snowboarding. I'll...

Goal is to mountaineer snowboarding. I'll use it for multiple purposes and I have been trying to figure out which I should get... Alpha SV, Alpha LT, or Theta AR??? Price seems to all be about the same (SV a little higher). Help please...

Best Answer

I like the Alpha LT for mountaineering. Its the lightest of all 3, and the Alpha style fits me well. The only difference between the Alpha LT and Theta AR is the fit and some nylon differences. Theta runs a longer which I dont really like because I am only 5'8". It does have thicker nylon reinforcements though so it is a more durable jacket. Uses 80 D nylon on the high wear areas such as the shoulders. The Alpha SV is all around a more durable jacket. I like the SV = Severe version of Arcteryx line on my pants. They tend to take a beating more and I only have one layer under them. I like my jacket to be a bit lighter, and breathe more as that's where there tends to be more layers for me. All in all 3 great jackets just slightly different uses and or what you prefer.

If you want the lightest of the light take a look at the Beta LT. . Definitely been stripped down of a few things but I figure when I ski mountaineer I dont really wear my hard-shell all that much. Usually only on my way down generally, I am hiking in a mid or base layer. Sure on stormy days you will need the shell to use on the way up possibly but, just to block snow and wind. Since your walking up hill you will still want something extremely light that breathes well. This is one of the lightest if not the lightest Gore-Tex 3 Layer Pro Shells. They removed pit-zips and its not as long as the Alpha but, at 10 oz it feels real nice in my pack. They are made out of the same nylon so If I were looking at the LT I would give up the pit zips and extra length to drop the 3 ounces. Ill leave the other jacket questions open so someone will see them and add their opinion hopefully.

Hey Richard, Bill is spot on with that answer. It can really boil down to how you like the jacket to fit. Since you're in the mountains with changing weather the jacket does spend a lot of time in your pack I've found. For that purpose alone you don't need extra pockets and do want to save weight and bulk.

At the same time if you're going to be using it for resort snowboarding an equal amount you'll want vents and some pockets.

The I prefer the Theta line because I'm tall and need the length. When splitboard mountaineering I take along the lightest hardshell I have because its going to be in my pack the whole way up unless it gets nasty out.

Hi! I am 6 ft tall, weight 170 lbs and...


I am 6 ft tall, weight 170 lbs and have a 42 in chest. I have tried the ALpha FL and the M was a bit too snug (it would be hard to layer under) and the L definitely too large for my stomach. Do you think a Alpha LT in M will fit me?