Weather for flying in winter....the dark time! Days short, fog, sun very low, and often interfering with visibility.
Flying at High Wycombe, they used to turn on the lights and practice night flying... In the USof A, the PPL license does not require a special night rating. Here in the UK it does.
Seems to me that if you can find someplace to have a go at night flying it is a useful additional skill, especially in winter when there is plenty of dark time. And then if you contemplate flying in the US, you would have an idea of what it is like.