Highs in the summer are perfect on average.. But.. it does get really hot. We rarely hit 90. Our humidex raises the feels like really high. It's the humidity that gets to you...I'm thinking you need to relocate.
I looked up your area on a map - mental note to not move there. As a CA native, I'd freeze to death. And I thought Wyoming was cold. What are your highs in the summer?
Mid 70's to mid 80's is average June-Sept weather. Usually nights get down to 50's in the summer.
We're very similar in climate to Maine.

