mid layer recommendations and vest

It depends on the person. I run hot, so Patagonia R.5 + Thermwrap Vest + Houdini + good hat works to 25F on backpacking and snowshoe trips.

I know a number of people who won't find it enough anywhere near warm enough for 25F… and I recently discovered that if I haven't been active during the day it's only good for me down to around 35F. This was discovered on a trip with my family when one of the days I was mostly reading and then I went outside for to watch the snow fall.

–mark

I prefer merino wool to synthetics because I find that it keeps me more comfortable and regulates temperature better in a much broader range of temps. With a wool 2 zip-t and a wool 4 hoodie, I'm good with a shell and an insulating piece. If I'm active-active I'll probably just be in the wool 2 and maybe wind shell to that ~25*. Less aerobic I'll toss on the wool 4. If I'm more sedentary I need some kind of down vest or jacket to toss on over. Big fan of the Western Flight Jacket and Vest, Nunatak Skaha.

If you're taking something like the Flight, your R1 is plenty warm as a midlayer. Cheers-

Short answer is yes, the R1 should be warm enough while active.

I just got done doing two snow camping trips with the R1 hoody as my midlayer. 1st trip was snowing and mid-30s. I wore an REI polarmax 1 tee as my base, the R1, a Montbell UL Thermwrap vest, and Alpha LT jacket. I was plenty warm snowshoeing. Found the vest to be pretty sweat-drenched when we reached camp. Minus the vest, the rest kept me warm while setting up our Megamid.

2nd trip is more relevant to your query. It started out sunny, temps in the high 20s, quite breezy. I wore the Polarmax tee, the R1, and the Houdini. Granted, we were breaking trail through 18 inches of snow, and gaining 1000' of elevation in a mile, but I stayed warm but not too warm in that combo. It kept me comfortable during rest stops of 5-10 minutes without getting chilled. At camp, as the sun disappeared behind cloulds, I had to throw on a synthetic fill jacket while waiting my turn to dig our snow cave.

Higher than 45, I find the R1 too warm.

Hope that helps.

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