10 degree or 20

[FreshStart]

So my wife has a 30 degree top and bottom econ quilt used in Vermont on the long trail in the summer and loved them. The plan right now is to start our AT thru next early March. If her job doesn't give her the time off though she will be finding something new when she comes back so our time frame might be a little more flexible but we would still be leaving by the middle of March. She is really stuck on whether or not to buy a 20 degree or 10 degree set of quilts because the 30 definitely won't be warm enough especially if we have another winter like the one we had this year. She isn't a super cold or hot sleeper and has a wool sleeping layer and a puffy that she could layer on top but we are trying to get an idea from others if the general consensus would be that 20 degrees is not warm enough. Personally, I will be using a 20 degree set but I sleep warmer than she does.
Her other idea was a 10 degree under quilt and 20 degree top. I realize sleeping is a personal thing but any feedback would be appreciated.

[Red Wing]

10. Especially after repeated stiffing.

[HandyRandy]

The reason I really like a 20° is that I can use it indoors or up to about 70° which is about the temp at which you can pretty much get by without an UQ if it gets any warmer than that. It's not like down UQ’s are all that heavy or significantly more expensive to bump it down another 10° or 20°. But the packed volume is definitely worth noting. If you have the pack space, extra down is often worth carrying.

Good luck on your thru-hike! I want to thru the AT as soon as I get the chance!

[Red Wing]

FFT. People never account for convection when gauging temps. 30 degree forecast, most would take their 20 degree quilt. Except toss in a 10 to 15 mph breeze and you get a real feel of 15 degrees. Now your 20 bag, in 30 degree temps isn't keeping you warm.

Add on extended use.

If it were me. No question. Tbh I'd probably do a 20 with a few ounces extra. That'll help with the repacking over and over.

[Malcolm]

When I made my decision, I checked out historical average temperatures for my area. Specifically, the average low temperature was really helpful for determining how cold it was likely to get in my area during the months in which I'd like to camp.

That led me to get a 20 degree underquilt. Now I wish I'd gotten a 10 degree quilt to extend my season and deal with temperatures lower than the mean...

[Tyroler Holzhacker]

If you camp deep into the shoulder seasons or maybe even winter camping, you might like a zero degree UQ, and also use with a 20 degree TQ. For the summer, get a 40 degree UQ . If you live in the South, you may only need a 20 degree UQ all year long.

[Peppy]

You have a 30, go for the 10, she’ll have a lot of versatility with the 2 options!

[Hefty Hanger]

You can plan a weekend, but a 4 to 6 month through hike? Remember you will be getting into some elevation also, which will be colder. Personally....I'd go with as low as you have space for. Plan for the worse, hope for the best is my rule. LOL. Good luck!!!!

[Nedh84]

You have a 30, go for the 10, she’ll have a lot of versatility with the 2 options!

This is really good advice I think as long as she can actually fit the 10 in her bag. But yeah the space and weight difference is going to be negligible between the 10 and 20. Easily saved by making other smart packing decisions.

[FreshStart]

This is really good advice I think as long as she can actually fit the 10 in her bag. But yeah the space and weight difference is going to be negligible between the 10 and 20. Easily saved by making other smart packing decisions.

What are everyone's thoughts about a 10 degree UQ and 20 TQ? I'm not sure about the room in her pack. She has an osprey aura 50 but she's been considering the ULA circuit, which is a 65L.