Usually there is sunny and warm (sometimes hot) weather from June till August in Pszczyna - add some rains.
From September till May it depends on your luck hehe. Look at Fernando in castle park at... unexpected snowstorm in April 2003.
Unique Suggestions: Take it easy, keep smiling and be happy like Fernando was :-))).
Fun Alternatives: Visit Pszczyna from May to August.
It's real tourist trap in my opinion. You must arrive to visit famous interiors of Pszczyna castle before 2 pm at least on business days. They are opened till 3pm but you will NOT be allowed to come inside after 2pm.
There are no English or German speaking guides unless you book them in advance: call +48 32 210 30 37.
Unique Suggestions: Check up-to date opening hours (depends on month and day of a week): click here then click on "Opening hours" on left and choose a day when they are opened longer.
Buy a leaflet/book on the castle available in English and German at the entrance and visit the castle's interioriors on your own.
Fun Alternatives: Enjoy the castle from the outside and the castle park like Donald (DonGrafton) did.