I’m surprised no one mentioned that you need to wind your fireline on as tight as possible. This is critical to prevent the line from digging into itself on the reel. If it digs into itself, it definitely won’t come off very easily.
Also, in cold weather, super lines as a whole are not going to come off your spool very well. By cold weather, I mean at or below 32 degrees. Under these conditions, your much better off using a good mono line.
Reel Magic will also help on both super lines and mono lines when fishing in freezing weather conditions. Spray it on the spool and your line guides. It helps prevent the line from soaking up so much water. Less water on your line means less water on the rod guides and in your spool.