The trigger tech trigger can handle dirt and dust well but no help if the safety ices up. The Gentry from the above post might be the only option to eliminate the entry point. I have not had this happen but I don't hunt in severe conditions much. I have had the exterior ice up but it didn't get into the safety cut out.

Maybe pair a Gentry safety with a TT Trigger?

"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli