Your injury description and weather description certainly sound like leaf spot. If you're not managing a high-end surace that's going to be on high-def TV in the next week or so, fungicides are going to cost you more than what you'll get out of them. Back down on the N fert and look for ways to improve drainage in super wet areas. If its just raining too much, that's something you'll just have to deal with.
You'll grow out of this damage when the rain backs down and the sun starts hining again.