The Okanagan is the driest place in BC. That said you've had a really wet year. We've had the same never ending rain over in the Kootenays. Really with a good tarp and UQ protector from 2QZQ your fine. Even without the UQP. The longer your out in the winter the more of an issue it can become because of moisture accumulation in the quilt,,,but in the temps the Okanagan usually gets in winter if your going out for a few days you shouldn't have a problem. I would only consider synthetic if on the water. Full length synthetic is allot of bulk. Your big issue will be will you get much snow. Typically the OK doesn't get that much but who knows with the weather these days. You've probably done this but pull up a weather site for vernon and look at the winter normal temps for Nov to march.
A O degree quilt will be tons or 20f degree with over stuff to get you to 10f Our winter lows are kind of in-between. Anyway good luck. Been thinking of a full length myself but going to stay with the winter yeti for now,,,,,,,i think (-;
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