It gets pretty nipply here as well. I switch to a "special Mono" I have because, thread leaders were freezing to rocks while I switched out flies. The special mono is very supple and performs as delicate as thread though. It doesn't seem to ice up.
But did make some fluorocarbon leaders as well and used them a couple of weeks ago on stillwater (yes I said stillwater, but freezing) I too noticed bad icing with the fluoro, but I assumed it was because of haveing the rod half submerged in my pontoon. I wish I had taken pictures of that. The guides had HUGE ice cubes.
Oh, John, no fair posting the same fish...LOL http://www.flyanglersonline.com/bb/s...tymology/page3