That looks like a typical case of leaf spot. I am told it is a good
idea to remove the portions damaged by too much rain. Next season,
your foliage should be fine. We have to put up with leaf spot every
since we moved back to the west side of the Cascades. From time to time
we spray to reduce the amount of leaf spot.
Apparently it is a fungus born in the soil and when it rains hard the
droplets transfer the fungus to the leaves or so I have been told.
Perhaps someone out there has a better explanation.