Originally Posted by lookitsma
My guess would be that you're battery if you've never replaced it before. Battery life and so forth are varied depending on ambient temperatures. Batteries tend to discharge more quickly in the cold as the chemical reactions in batteries are slowed down when ambient temperatures are low.
I had a lot of friends who were stationed with the Army in the Alaska and they told me they had to get a battery heater and engine heater when temps started hitting -20 F (just shy of -30C for you non-imperial users.)
This... Get a new battery