How to deal with temperature swings while sleeping in a tent?

Question

Unlike homes, temperatures in a tent fluctuate wildly. It could easily be 20 degrees Celsius at 9pm when you’re off to sleep but then only 5 degrees when you wake up in the morning. This causes an uncomfortable balance: if you go to sleep semi naked, you’ll wake up at night shivering, interrupting precious hours of peaceful sleep; on the other hand if you tuck yourself in for 5C, you’ll be sweating up very quickly making it hard to fall asleep in the first place.

Are there any tricks experienced campers use to deal with this? Or does everyone either sweat before sleep or wake up at night to add another layer?

Answer 1

I am going to disagree with the frequency and surety with which you predict these temperature swings, but they do happen. Typically it gets colder as the night goes on, which is a shame because it's easy to kick off extra covering while only partly awake, but harder to add more.

Nonetheless, here is what I do:

• I leave my sleeping bag unzipped, and when I go to bed it may not entirely cover all of me. As the night goes on I can pull it up over my shoulder, pull my leg back inside, etc.
• I keep a coat or towel in the tent, and can put that over my sleeping bag if it gets really cold
• If I am expecting a cool night, I can keep a sweater inside my sleeping bag with me. That makes it easy to find and pre-warmed when I put it on.
• Since I share my tent, I also share my sleeping bag. We can move closer together when it's cold and further apart when it's warm.

I have woken in late August to find it was 0 C. We had already pulled the sleeping bag up over our faces and still were woken by the cold. In that case getting up in the pre-dawn twilight and moving around is the only real solution, when all you have is summer gear. We were car camping, so we got in the car. Had we been canoe camping a fire would have been in order.

Answer 2

Here in Scotland it never really gets cold; getting below -10C is pretty rare, and in the summer here, because the sun doesn't set until very late (after 10pm in mid-summer) trying to get rid of excess heat is my first concern. I find in a small solo tent I generate far too much heat so an unzipped sleeping bag over me that I can kick off is essential.

In a larger tent, eg if camping with the family, the temperature may vary a bit, but again, after an initial cooling , the temperature remains fairly constant, so the two person sleeping bag I share with my wife tends to end up with her side covered up to the neck and me uncovered from the waist up.

Answer 3

In four decades of backpacking, I don't think I have ever had a totally uninterrupted night or a totally comfortable night. I found the rewards of being in the outdoors so great that I just ignored minor inconveniences and discomforts.

But that doesn't answer your question. And minor is subjective.

The short answer is: ZIPPER.

First, the scenario you present is of a change of 27 degrees Fahrenheit from evening to morning. (68 F to 41 F). I have never experienced such a large shift, and it would be unusual where I have done most of my backpacking (Rockies, Sierra) unless you retire while the sun is still high in the sky.

But let's assume that you have. I agree that you can't go to bed dressed or undressed for 68 F and sleep through a drop to 41 degrees Fahrenheit without waking up and changing something.

If it is very mild when you retire, try sleeping on top of your sleeping bag wearing enough clothes to be comfortable. When it gets too cold for that, go into the bag, with the zipper only partially zipped. As it gets colder, zip up the bag further. If your bag, fully zipped and inside a tent cannot keep you warm at 40 F, you probably need a warmer bag.

Thus, I think you need make only two adjustments which you can do while only semi-conscious to be comfy through the night.

Adjusting the zipper on the tent opening is also a solution, but is not as easy to get it right.

More annoying is when you decide to sleep outside the tent because the weather looks fine, and it starts to rain soon after you sink into REM sleep.

Answer 4

Even at home, I will add/subtract covers during the night. Mind you, I sleep with the window wide open.

I go to bed knowing that the temp is going to go down.

• I usually sleep in polypro longjohns -- top and bottom. These give me draft resistance. This won't be true if my tarp is at 20 degrees C.

• I have a toque or balaclava at hand.

• I start the night with the sleeping bag zipper unzipped. If I wake up chilly, I'll zip it up. If I wake up hot, I'll unzip. If zipped up and I'm still cold, I'll put on my toque. If I'm still cold, I'll call the dog over.

Answer 5

I think that the most extreme temperature swing I experienced in a tent involved 15 degrees C. Besides the zipping/unzipping what I've found to be helpful were:

• getting my head warm: not only covering-with-sleeping bag warm, but actually putting on a cap
• getting my face covered as much as I can: from my experience that is a surface which can lose a lot of heat, so I try to get most of it zipped up in the sleeping bag. Might happen that breathing can get the sleeping bag damp, but until now I did not experience that
• I keep 2 layers under my head as a pillow, and, as suggested above, one in the sleeping bag, it keeps me warm and it stays warm in case I have to put it on
• might be a girl thing, but I personally found it helpful to put one extra layer around/under the hip area. Some sleeping bags designed for women are enforced on that part
• having a zip on the bottom of my sleeping bag helped me unzip and cool down without being needed to unzip the bag completely (and then getting it off part of my back). Also it helps to put on an extra layer of socks if needed, without letting out all the warmth in a critical cold moment of the night.

Answer 6

It's possible to adapt yourself a bit, to get used to fluctuating temperatures, if you don't keep your home such a constant temperature. Partly this is temperature tolerance, but partly it's getting used to making adjustments while half asleep. dealing At home, I use the same quilt and (lack of) sleepwear year round, though the bedroom temperature can get down to 12°C (54°F) just before the heating comes on on a cold winter morning, and in summer can reach 30°C (86°F) at bedtime, or a bit higher in a heatwave. Adaptations are of course required at the extremes - a blanket to make sure the foot end is closed, or starting uncovered. The summer case is most relevant as with the windows open the temperature will drop quite a lot overnight, but you can get used to covering yourself up without fully waking.

Of course a bit of forward planning is needed, but it's also better to wake up a little cool and adjust, rather than to sleep so deeply you're shivering by the time you notice you're cold. I'd really try to avoid sweating in a sleeping bag as you've then got a damp bag (and/or clothing) to deal with, which won't be fun if it is chilly closer to dawn or the next night

Answer 7

A tarp makes the best all season any weather shelter. Each occupant needs an overhead line or inside support in his corner to keep the tarp above his head.
A centre or side chimney supporting the tent. 2 pegs on each corner attached to tie points 4” from tarp edge about 12” apart. Poles can support all sides which can be raised to make a shade in hot weather or the sides kept tight to the ground in a winter blizzard. No doors are necessary but eye level peek out vents are good.