Ninjamini,
Hard to say about temps and humidity. Look at historical data for an idea. At least you will have the fan to help move air if needed.
Besides the "Dells" check out Baraboo, and certainly the "Forevertron".
http://en.wikipedia.org/wiki/Forevertron a true piece of Roadside America.
A day trip to Devils Lake State Park, to me a beutiful place.
Also, a very short ferry ride for something unique at Merrimac, Wi.
http://www.dot.wisconsin.gov/travel/water/merrimac.htm
Merrimac Ferry
Merrimac Ferry, Colsac III.
Merrimac Ferry (Colsac III) is open for the 2013 season. The ferry will remain open 24 hours a day, seven days a week, until ice forms on the Wisconsin River.
Is Wisconsin's only FREE ferry.
Merrimac Ferry crosses the Wisconsin River between Sauk and Columbia counties.
Shuttles WIS 113 traffic 24 hours a day, seven days a week, between Okee on the east bank and Merrimac on the west.
The ferry holds 15 vehicles at a time, in addition to bicycles and pedestrians, and last year (2012) ferried over 282,000 vehicles across the river.
A single crossing takes about seven minutes.
Hazardous materials, including but not limited to, agricultural nitrogen, propane in excess of 100lbs, fuel in excess of 100 gallons, ARE NOT allowed on the vessel.
Emergency and/or planned maintenance closures of the ferry will be posted on the Wisconsin 511 Travel information website.
Jean