The 15 Best Winter Jackets for Extreme Cold, So You Won’t Be Left Shivering

It’s hard to say which is better overall, natural insulations or synthetic insulations, but there are some specific scenarios in which one definitely stands out over the other. For example, Johnson notes that coats made with down feathers are much lighter in weight than synthetics, and the weight-to-warmth ratio of down is remarkably high (meaning it’s shockingly lightweight considering how much warmth it provides). Down is also easier to pack if you’re headed on a trip or want to stow your winter gear for the summer. “It readily compresses and re-expands to full fluff more quickly and more readily over time than synthetic insulation,” explains Johnson. “Down jackets are therefore easier to move about in and easier to pack than other garments of similar warmth. Properly cared for, they stay closer to their original warmth level than a synthetic jacket over the same number of years of existence and days of use.” Wool is also a great natural fiber for winter because “it continues to insulate even when damp or soaking wet,” meaning you won’t suddenly start shivering if your wool sweater gets wet.

That said, there are some notable downsides to natural insulation, most notably cost—natural materials tend to be much more expensive than synthetics. “However, if a garment works better and lasts longer, it is worth the investment,” suggest Johnson, “and might pay for itself several times over in the long haul if you do not need to own as many different clothing items or do not need to replace them as often.” There’s also a higher chance that clothing made with natural fibers will require special cleaning instructions.

Synthetics do have one major benefit over natural fibers, which is that they have been specifically designed, from scratch, to serve a very specific purpose. So while down feathers may be lighter and warmer than down alternatives, they’re also totally useless when wet, whereas basically all synthetic downs are designed to maintain their shape and warmth even after being exposed to water. As Johnson notes, this makes it a particularly good option for wet, moderately cold climates, “for example, the rainy upper-20’s-upper-30’s that passes for winter in much of the Pacific Northwest. It is also better than down (though not as good as wool) for highly aerobic activities because it will not ‘wilt’ and lose some warmth from sweat.” On the flip side, generally speaking, synthetic insulations are not often the most eco-friendly choice. “While more and more brands, especially in the outdoor industry, are offering garments that contain some recycled material, there’s still environmental impact to every garment you choose.”

“The three main variables for shell fabric are waterproofing, breathability and durability,” says Johnson. “How much each matters to you will depend on weather conditions and type of activity. Weight is another variable. A lightweight garment in good standing for all the above qualities can be considerably more expensive than a heavier one. Whether you need to pack and carry the garment or how far and fast you intend to move while wearing it will help determine priorities.”

As mentioned earlier, down feathers lose a lot of their warming ability when wet, but there is an incredibly easy solution: Choose a winter coat with an outer layer that’s waterproof or water resistant. “Most shell fabrics are nylon, usually with a water-resistant layer called DWR (durable water repellant) on the outside that helps precipitation bead up and run off,” explains Johnson, but it’s always a good idea to double check the specifics of your coat before ordering. If you live someplace where the winters are equally wet and cold, a water resistant jacket won’t work as well as a waterproof one.