I do not know if this is considered a superstition or a religious tradition, but it is one that I followed on my wedding day. If you want a sunny wedding day, it was a good idea to place a figurine of the virgin Mary in your window the week before the date. This was to help guarantee that the day would be sunny and wonderful in many ways. Hope this is one that can be shared. It worked on my wedding day and others in my circle of acquaintances.