Great - bring wind! We have almost forgotten about wind this summer.
I think you'll be able to use the 130L, and the even the 85 L on the windier days. Many guys and gals get several sessions a year on their 85 L boards. Jeannie (light weight) has a 5.5 m2 and 85L as her 'bread and butter' kit.
Welcome to MI Windsurfing! Well, Michigan is not the gorge, but we do have some beautiful fresh water to sail in. Your Northwave stuff will work well in the Great Lakes high-wind days. I think there's a few pics on this site of guys using Northwave on Lake Superior.