Is Dalian any snow on November and December? And how is the temperature on October?

Well, according to the previous weather statistics, the possibility of snow in Nov.or Dec. would be low. There may have several snow days in the middle of Jan. You can keep close attention to the forecast before going there.
In addition, the temperature may range from 10 C to 20 C in Oct. It would be cold. You need to prepare overcoats, sweaters, pants and other winter clothes.
Hope helpful!