I'll be going to the BWCA in a couple weeks. Debating with myself if I should take the climashield underquilt that I made, or go for the extra bulk of the winter weight JRB down.

I would make sure I have gear for mid 30's. When we were up two weeks ago it got down to 41 one of the nights. I was using a homemade down quilt that is overkill, my son had my climashield jarbidge. That night he put on his long johns and he said he was not at all cold. The ting with underquilts is that you can always vent them. When deciding on what quilts to bring I am always sure that I have the worst case scenario covered. If you are going to be bringing enough warm clothes go with the lighter quilt, if you are worried about it I would take the warmer one.

We were up there at the end of July, and I made sure to have my Winternest. I left the head loop open for venting.

It seems like the down adjusts somehow to warmer temperatures, allowing more heat to escape.

Along with Dammfast, I agree that it's easier to open up more insulation than to manufacture heat iin the wild.

The warmer quilt is the way I was leaning. I'm just annoyed it's a bit bulkier.

I've experienced frost in the Boundary Waters in early August.

By September the "normal" temperature ranges from the low 30's at night to mid-60's in the day. It doesn't take much of a cold wave to get "below normal" night time temps down in the twenties.