advice!

I don't know if asking the blog world for advice will really work (i don't know if many people read my blog) but I need help/opinions!

Our wedding is at the family farm out in the country, down a dirt road bordering the national park. My problem has to do with rain. In the case of a light rain, we have tents we have reserved to cover the ceremony site and the reception. In case of a heavy, soaking rain or gale force winds I have found a place that we have the option of reserving, the rappahanock community center down the road. Here is the problem. The wedding is September 5th. Currently no one has reserved the community center but we still have 7 weeks to go. For me to reserve the community center so no one else books it is a non-refundable $500 fee! Do I hand over a chunk of cash for my peace of mind or do I hold my breath and pray that it hurricane whoever doesn't decide to roll up the east coast? Or if the hurricane does roll on up the east coast do I hope the community center has not been booked! Help!!!