what it it likely to be the weather from the 12th November
Nobody can possibly forecast day-to-day weather with any accuracy so far in advance.
You can get a rough idea of what to expect in Krakow in November from the climate averages here:
When your date is much nearer (say, around November 1st) check the weather forecast to get a better idea e.g.
You can be pretty sure that will be chilly to cold, that at least some rain is likely and that there may well be some overnight frost. How cold you personally feel depends entirely on what type of climate you are used to.
It's best to pack clothes you can layer (several thinner layers are warmer than one thick layer) + warm, waterproof or water-resistant outerwear + hat, scarf, gloves + sensible footwear which will keep your feet warm & dry but also allow you to walk easily. Central, historical Krakow is very walkable indeed and you will see much, much more if you walk as much as possible.
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