swinging shouldn't be a problem if you are doing the russian swing (maximum shoulder height).
For the more advanced exercises military press, snatch and clean and jerk you need a room where you can stand up with your hands straight above your head.
I am training outside the whole year, but it doesn't get extremely cold here in winter -5° to -10° Celsius is pretty much the minimum. But I am under a roof and so it works for me (but I have to store the Kettlebells indoor so the handles are warm).
For the more advanced exercises military press, snatch and clean and jerk you need a room where you can stand up with your hands straight above your head.
I am training outside the whole year, but it doesn't get extremely cold here in winter -5° to -10° Celsius is pretty much the minimum. But I am under a roof and so it works for me (but I have to store the Kettlebells indoor so the handles are warm).