GoLite Beartooth 650 Down Jacket - Women's - 2009 BCS

I'm in the same boat as you, trying to find a warm jackets for backpacking in the Sierras above 9,000ft ... I can't figure out from the description if this has a hood, the description says yes/no - I'm not sure what that means.

For me it is hard staying warm on the cold Sierra nights at altitude, so a hood is a must. The "Mountain Hardwear Sub Zero SL Hooded Down Jacket - Women's" it is the same fill but is costs a lot more.

Both of these jackets are not water-proof, so need that too, you'll have to layer a shell over this.

Tough question to answer because it has to do with personal preference, body shape, and how you plan to use it. In general the XS is PROBABLY suitable for this “body size” (especially if you are planning on using it for casual purposes) but if you need more room for extra layering or to account for a more curvy figure the size S may be a better choice. Note that this is not an overly generous cut in this style but it is a bit longer than some similar styles as mentioned by sst3021840 so, unless you are very long-torso’d, the length will most likely be OK –even in an XS. Regarding the Lt. Cypress color, it is a bit more vibrant than it looks in the image but is still pretty pale – definitely not “sea foam-ish” though. It's a really cute color - in my opinion!

The length from the highest point of the shoulder (basically where the shoulder seam meets the collar) to the bottom hem of the jacket in size M is approx 24”. XS will be about an inch shorter.

I am not sure of the exact length but if you have a long torso I can assure you this will be a good purchase. I'm short with a small torso but I have about 3inchs to spare at the bottom. Hope this helps