Musicians: how do you deal with outdoor weddings in hot/cold/rainy weather?

Hello, new here, I signed up in order to ask this question: these days it seems like, due to the economy perhaps, more brides are planning outdoor weddings without backup indoor alternatives. They just think it won't rain or it won't be too hot or too cold. We have decided we don't want to be doing outdoor weddings when the temperature is over 90 degrees or under 57 degrees. What do other musicians do in this situation? What does your contract say about temperature? And if it is just too hot to play outside, what do you do? Thanks!