Engines do tend to run better in cold weather once the engine has warmed up to operating temperature.
During cold weather an engine may run a bit rough for a few minutes until the engine gets heated up and then the engine will run better.
My truck does this and is fuel injected.
During cold weather it can sometimes be a bit hard to start and then I have to let the engine run a few minutes or it will run rough and die out.
This is because the coolant temperature heats up a sensor called a coolant temp sensor which tells the computer on the vehicle how much fuel needs to be sent to the engine.
So the engine can get too much fuel at first and then as it warms up it gets less fuel and runs properly.
The colder weather should also help your engine run a bit cooler as well because the cold weather helps cool the engine off.
With carburetor based engines you had to let the engine warm up for a few minutes or so before you could drive off because the engine needed to be warm or it would stall.