Back when I reviewed outdoor gear professionally, which is to say I regularly got stuff for free and was paid for writing about it, and is not to say that ever amounted to a sustainable living, trips like this were as rare as they were lusted after. Outings where conditions were so bad, so consistently harsh, that every detail of your protection was made plain; bad, good, and in between. In even harsh climates it’s as tough to find these trips as it is people who can both make a living from gear writing and keep their integrity. This rare, I’ve come to realize, regardless of context. There’s a ceiling for honest gear reviews, directly related to number of days in the field. Shortcutting knowledge from experience is impossible, but not all days bring equal learning, and there’s little better for learning about midlayers and insulation than 72 consecutive hours of cold rain. I’ve contemplated how many legit reviews one person could do in 365 days, and without a big travel budget to jump around to different, differently bad climatic episodes the answer is, not very many.
In Montana 2017 brought the warmest July on record, and a summer that went from mid-June to early September without meaningful rain, localized thunderstorms only. These scorching months turned the abundant grass of a deep winter and wet spring into tinder, and the irony of a big winter birthing an epic fire season was as deep as my biggest hunting trip of the year coinciding with an early stretch of deeply autumnal precipitation. I got soaked for three days, put my plan B for access into effect to avoid impassible muddy roads, ripped the derailleur off my bike anyway, and upon return spent hours in the yard hosing off everything; from rifle scope to backpack to packraft. Thankfully I found animals when the sun finally appeared, and thankfully I had on a whim brought along my brand new Patagonia Nano Air Light Hoody, which proved to be the best wet weather midlayer I’ve ever used, by a large margin.
I’ve written a bit about the modern trend of active insulation; synthetic fills whose attributes and construction allows for breathable shell and liner fabrics. Up to this point my conclusion had been that while these garments have done a good thing in complicating the insulation conversation beyond merely equating high R-values with best warmth, at best they came close to approximating the function of fleece plus windshell in a streamlined and potentially more user-friendly package. As recently as this spring I didn’t see them as likely to function better than fleece in difficult conditions.
I was wrong. When Steve House says it’s one of the best things Patagonia has ever made, he is in no way kidding. The Nano Air Light Hoody outperforms every type of fleece I’ve ever used, in every way about which I am thus far qualified to comment. It’s a joy to see a company whose activism and heritage so often contrasts with the frumpy plaids that pay the bills make such a forward-thinking, no-holds-barred technical piece. One whose full value is probably all but impossible to explain to the casual consumer, who feeds the increasingly fat beast which is the outdoor industry.
I wore the Nano Air Light Hoody for 100 hours almost straight last week; while hiking, glassing for hours under a tree, sleeping under a damp mid, cooking and waiting out downpours in the same tent, packrafting in 20 mph winds, mountain biking, and carrying 90 pounds of meat and gear 6 miles up a big hill. I had it off for 2 total hours, when the warmest and sunniest hours of the weekend thankfully happened to coincide with the time I was butchering and doing the initial packout of my sheep. The Light Hoody was warm under a rain coat while stationary, cuddly inside a sleeping bag, breathable under the same rain coat while hiking, and dried in a way which was nothing short of astonishing. Islands of moisture within midlayers (indeed, all layers) are a small thing that can make for big misery during sustained wet weather, when you have nothing more than body heat and the occasional hot water bottle to dry things out. The Light Hoody has virtually none, only the cuffs hold moisture and dry slower than the rest of the jacket, and they do every well for something with 12% spandex. Adding and subtracting layers in the rain is always problematic, but being able to spend a day hunting in 50 degree rain, wearing the same three upper body garments with no more concession for activity than adjusting zippers and hoods breaks all the rules, but the Light Hoody made it happen.
Construction makes almost as big a difference here as materials. Patagonia claims the shell of the Light Hoody at 70 CFM (cubic feet per minute), which is massively breathable, almost enough that it should be useless. And the Light Hoody doesn’t block the wind in a way most would understand, rather it vaguely mediates how much wind reaches your core. This allows the Light Hoody to dry fast, faster than any fleece I’ve ever used, and gives you the option of bringing it up to more fully windproof with other layers, as well as choosing whether evaporation or transpiration will dry things out. The slim fit, deep partial zip, simple chest pocket, and lack of a waist drawcord tunnel or any other material layered beyond what is absolutely essential maintains and enhances that breathability. The Light Hoody kept pace with, and probably exceeded, the Sitka Core LW I had next to skin, which is the first time I’ve ever been able to say that about an insulating layer.
I hesitate to be dramatic, but I’ve having a hard time imagining when I would take fleece out into the field again. The Light Hoody is expensive (I bought it half off), and the durability of the insulation is an open question, but when something this potentially important works this well it is hard to be anything other than excited.
Add: I’ve received a number of requests for specific comparisons to other garments I’ve used, so this is that, along with a few more specifics on recontextualizing insulating layers and warm in the outdoors, generally.
Warmth in the outdoors is often understood as an overly simple concept. Static warmth for a dry, stationary body requires only decent fueling and hydration and enough layers. Dynamic warmth, where said body is in various states of motion through varied environments, is governed by the same rules, but they are interrupted by the need to protect from external, while venting and moving internal, moisture. Achieving a balance between external protection and internal insulation is, most of the time, the key to sustainable activities in the outdoors.
This is what I wrote back in 2015, about the original Rab Strata. The Strata epitomized the original approach to active insulation; 80 grams/meter Alpha, an uncalendered but otherwise traditional nylon shell, and a mostly mesh liner. The Nano Air Light Hoody seems similar on paper, if more lightly insulated, but in the field it feels drastically different. The Light Hoody might be a good bit colder under totally static conditions, but it manages moisture so much better and dries so much faster that they have similar effective warmth. With the Light Hoody shell and insulation combo so much more breathable than the Strata, and down and down blends so much warmer, I can’t see a place for something like the Strata.
Until a few weeks ago I would have used either a 100 weight microfleece shirt, or an older Patagonia R2 vest, as an insulator and buffer between the hardshell and baselayer in protracted rain. And I never really felt either to have that many downsides, until the Light Hoody dried so much faster. I had the R2 vest with me during the hunt, but after the first day it stayed in my pack as an emergency layer, and served as a pillow at night. I’ll continue to explore what niches, if any, fleece will fill.
I’ve also used plenty of heavier fleece hoodies, largely as insulators for packrafting during cold conditions. Something like the Rab Novak (which I’ve since sold) was great for that (it was the only insulator I brought for the 2016 Bob Open, for instance). I replaced it with the even heavier Haglofs Pile Hood (380 grams/meter!), which is still in the proving process, and certainly nice for casual use, if massively bulky. 300 weight class fleece is certainly warmer than the Light Hoody, and while strictly speaking they are as breathable, they don’t dry as fast or pass moisture as well, which makes them, perhaps, a bit anachronistic.