Thanks for the replies guys. I think I will have a look at a flying school with different weather conditions at different times of the year, so maybe I get to fly in snow as well.
I would expect that the instructors take experience into consideration when deciding wheter to fly or not. I hope I won't stay grounded for ages due to bad weather, although given the amount I have to learn for the ATPL exam maybe that would actually not such a bad thing :-)
Stefan