Do you know what the weather is going to be like on your wedding date? Weather.com can tell you!
It's free and faily easy. After you create a user account on the website, go to the wedding module. The website allows you to plug in multiple days too. For example, I put in my August engagement party in Indianapolis.
The website will show you the all time high and all time low, averages for the month, as well as sunrise and sunset information. In addition, it will show the hourly tempature for the past three years.