December 10th 2013
This isn't so much a backpacking story as it is a good test of some gear I bought. It's my personal record for a low overnight temperature while hanging in a hammock.
I bought a Warbonnet Yeti from edcpreps off of the HammockForums.net. It arrived with perfect timing as we were expecting some nice Winter weather last night. As soon as I got home, I hung my HH Explorer hammock and attached the Yeti.
First things first, I thought the shock-cord suspension for the Yeti was pretty tight. I supplied my own mini S-clips and clipped it to my main suspension line just outside of where it attaches to the hammock. I'm not sure how far that is, but if it was three inches longer I'm not sure it would have fit.
I adjusted the UQ so that it would be under my head. It ended pretty much right where the bottom entry velcro started. So I didn't have to move the Yeti at all to get in or out.
The UQ is not asymmetric in any way like the HH Explorer is. At the foot, I was able to string the UQ's suspension line through the tie-out loop. At the head, I tried to clip it on using an mini S-clip but it kept popping off. It seems like I could probably snip the suspension sleeve at the tie-out loop and clip it on much better. I'm not sure if I'm ready to take scissors to my new quilt or not.
I have full-length Thermarest CCF pad that's about 42" wide I've cut in half. I had been using that side ways to wrap around my shoulders. Since the Yeti is only 2/3 length UQ, I used that under my feet. I also have some generic name mummy bag I got at Costco or something. I have no idea what it's officially rated.
I wore some fairly low R-value polyester hiking pants, wool socks, and a long-sleeved light fleece shirt. I also wore an 850 FP down jacket. I took with me some base-layer fleece leggings, and a second base-layer fleece shirt. I didn't want to overheat and sweat too much, so I didn't start off too layered up. I have lost my wool cap, and ended up using the fleece shirt as a hat.
I went to bed at about 10pm and it was 22°F. All night it fluctuated between 20-24°. I was able to warm up pretty quick and fell asleep in probably under 30 minutes. I woke up at midnight to go potty. It took a lot of motivation to unbundle and get out. I fell back asleep pretty quick though. I woke up again around 2am to the sound of snow on my tarp. I had hung it pretty close. I could hear the snow pile up and then slide down the tarp. I felt a little cold at this point. My legs were mostly ok, but my back was a little cool. I fell back asleep though and woke up again at 4am to the very loud sound of snow plows. They kept going back and forth near my house and I couldn't fall back asleep. I was also quite cold at this point. I started shivering and decided to go back into the house at that point.
Laying there awake in the hammock, I could see that pretty much the whole tarp had snow accumulation on it. When I got up and crawled out, I knocked most of it off so I don't know how much accumulated on the tarp itself. The ground outside had about 3-4" of fresh snow on top of the 1-2" that was already there.
My goal overall was to be able to sleep comfortably down to 25. I didn't really realize how cold it was going to get last night when I went out. Even though I went in a 5am, I'm pretty pleased that I made it through pretty much all night. I'm confident I could stay comfortable down to 20°F if I had warn more layers. Once I was all tucked in, I didn't want to add the layers. I think it'd be better to put on all the layers and take them off as I get hot.
This is very exciting to me. It's definitely the coldest I've slept outside and the first time I've slept out in the snow. This gives me a lot of confidence to do more Winter backpacking and camping.
I've got a lot more tricks to try like using a hot water bottle, a weather shield, a top cover, better top quilt, etc. But having the Yeti as an underquilt is a huge step forward for my gear.