About the road trip, from my city, it's not so far, just 8 hours of drive and I have winter tyres.
Is there so much snow? Should I take snow chains with me or would winter tyres be enough?
Hello. Weather report:
We have a thaw currently, a lot of snow is melting, you wont need chains.
Due to high humidity level, I would expect mists so careful there.
Roads are fine, frost is currently in the drawback so no fear of glaze, however it is slippery.
Winter tires in good condition highly recommended!
Have a great time in Poland.
As to your other questions, I think there is nothing in particular that you should be worrying about.
special tip: If you are going in Kraków, Lodz, Warsaw area (big cities) buy yourself anti smog mask.
It may be a problem, if you are not used to coal smoke.