Summering in the North

Sorry but I would not spend my summer in the Midwest (I lived 20yrs in MN). High humidity and bugs make it miserable. In fact I was there early July, had to get back to AZ where it was cooler (when you factor humidity) and less bugs. That area is great in the spring and fall though.

Best bet would be anywhere in the western mountains. Cool temps, low humidity, and not many bugs as long as you stay away from wet area's. CO is probably the best as it would be the closest for you but why settle on one area when there is so much to explore in CO.

Regarding the western slope of CO. You are going to have to get a lot higher than the 5000 feet that Grand Junction and Palisade (where we are) are at.
We have had low 90s to 100 degrees for weeks and the later part of summer is usually hotter than this part. The worst is yet to come!
The good news is that it does cool down at night to the high 60s or low 70s.

Also the swamp cooler (evaporative) will keep the house at 72 or 73 and the electrical bill is not affected much with that type of cooler.

Before we started our transition from full timing to snow birding we used to head to high country in Montana or Idaho in the summer.

Grand Titons National Park.

OP,check out Ruidoso, NM. Great weather, plenty to see & do, and not far from Austin....

I set my sights on Michigan as a summer destination (it is home, and family there) but most any place on or near the Great Lakes, or a small lake in Michigan, northern Wisconsin, Minnesota would work as well.

Doesn't even have to be a RV destination, small house on a small lake would work, or small house in town and a second RV for camping might cost less than moving a big one back and forth. Pretty interesting how much residential and recreational property is still available up there at "economic distress" prices.

Here in Pinedale Wy it was 29 degrees yesterday morning but the high 60's soon after. Next week it will be around 80 that the locals consider hot. Lot,s of things to do here and the beautiful Wind River mountains to look at. There is an awesome aquatic center and library. Great fishing and near to Jackson and Yellowstone. Great golf course too.

It is not unusual for me to have to run my heater for a couple of days (and nights) straight on the Washington coast. That is why it is referred to as the land of nature's air conditioning.

Estes Park, Colorado. Beautiful, cool, and great hiking. Close to Loveland, Boulder, and Denver if you need more activity.

Why not drive a little further to the Oregon coast. Summer highs from the low 60's to low 70's. Those temps should cool you off!

Island Park, ID. 13 miles out of West Yellowstone, MT. Between Georgia, Arkansas, Arizona and Texas plates, they are predominate plates in this park. By the way, at about 5 PM. yesterday it rained, sleeted, and snowed for about 15 minutes. Beautiful today, hit 70.