Canadian winters, I can expect temperatures as low as -30C. Though it's been pretty warm lately.

Here's my big problem. With underwear (boxers), long jonh's and my pair of waterproof marmot pants, the fabric of the underwear and the long johns tend to clump btween my skin and the seat, which create incredible chafing, sometimes to the point of opening a hole in the skin. Hurts!!!!

What can I wear to prevent this, that will keep me warm enuf for the winter here...