glass....graphite just wont cut the cold...Grump
I honestly don't have a problem with Graphite Rods in cold weather. Here in Colorado 20 below zero is common and with the vicious mountain wind it can be as much as 50 below with the windchill. Never had a problem landing 6 pound rainbows, 16 pound macks or 20 pound pike with graphite in the cold. The only two graphite rods I have ever broken ice fishing were from clumsiness.
I find graphite to be stiffer, more sensitive, and with more backbone than fiberglass. Therefore I do not use fiberglass rods for ice fishing.