Egret UL 20/30

My girlfriend is the same height and weight as you and she fits perfectly into her Feathered Friends Egret UL, size small, which is one of their women’s bags. It’s an excellent bag too - one of the best you can get.

Check out the Feathered Friends website in the United States. I bought a short-length Egret UL 20 for my girlfriend and it's great quality with 962 loft down, which is about the best you can get. The quality is easily as good as my Western Mountaineering bag, which is another highly regarded brand. My girlfriend is slightly taller than you at 161cm, but it's just long enough for her and it wraps around her very small feet so should be good for a woman of your height with average-sized feet. If you want to be warm down to 0C then I'd suggest the 20F rather than the 30F model. My girlfriend was warm enough in the snow on the PCT trail a couple of years ago, sleeping on the woman's version of the Thermarest Xlite sleeping pad. I live in New Zealand and had no problems getting the sleeping bag shipped here. I see a couple of recommendations below for the same bag, so there you go ...

As is evident from the variety of responses here, unfortunately, this question can only really be answered by your own experience with particular gear. In general women's bags are rated for "ISO comfort" and men's bags are rated for "ISO limit" as women in general, need a 10F (the approx difference) warmer bag than men (ymmv) Note that ISO ratings assume a ASTM R5+ sleeping pad and a full base layer. Feathered Friends don't use the ISO rating system but they are generally regarded as making warmer bags. For the Sierras in summer a 20F bag with an ASTM ~R4 pad is the default recommendation for most. The combination will be too hot in some weather and possibly a little cold at 5am at altitude...at least that was my experience as a man using a 20F men's down bag and an X-lite (ASTM R4.2) next to snow in May (Desolation Wilderness) and July (around Forester Pass) in a high snow year (2019). Generally I found it too hot going to bed and cool at 5am. Wearing a mid weight base layer worked best to regulate the temp. My bag is not ISO rated but seems to have a fairly accurate limit based on my experience camping in the low 20s recently. (ie. I was a bit cold but I wasn't shivering and it didn't keep me awake. A 10F bag will be too warm for most in most places in summer, probably not warm enough for actual winter camping and only really good shoulder season. Since it will be quite a bit heavier to carry all summer when you are likely to do most of your backpacking I would only get a 10F women's bag if you really know you sleep cold. In many places in the US a 30F bag is too warm for Summer. If later you find you want to camp in the winter your first upgrade should be a warmer sleeping pad. An inexpensive way to do this is to combine your R4+ pad with a closed cell foam pad (eg Z-lite, Switchback ~ASTM R2+) as the combination is equivalent to ~R6+ pad. You can also use a synthetic (eg 40F-50F) quilt over the top of your down bag which can help keep the frost off the down. Your over-quilt should be light enough not to de-loft your main bag. You can try a thicker base layer and also bag liners which help some people but can be more trouble than they are worth. They can work well with quilts to minimize drafts.

I thru hiked the JMT last Sept into Oct. Was concerned about shoulder season temps, so went with a 10 deg bag. It was overkill for 90% of my hike. You can always supplement with extra clothes, I'd go with the 20 deg bag.

Second this. It's a great bag. I actually got the small and I'm 5'4"

Third this! 5’3; love my purple Egret!

I thought that I was a cold sleeper until I upgraded my sleeping bag and got one that is the proper length (I am 5ft5 and got a women sleeping bag for 5ft6 women). It made an incredible difference in how the sleeping bag keeps and uses my own body heat. I got the Feathered Friends Egret 20 yf. I pair it with a Big Agnes Rapide Sl pad and it is now my preferred piece of gear!