Auspicious Dates

I'm an American Born Chinese and I don't really believe in superstitious things.  In the Chinese culture, sometimes people go by the lunar calendar and believe that certain days are good and bad for certain events.  Well, we had some dates in mind for the wedding and I thought I'd run them by my parents- little did I know that the date we had in mind was a really inauspicious day.  Too bad there was no clause in the calendar that picking an auspicious day would mean no rain!