What the internet can’t answer, good friends with the right data can.
In this case the friend is Adam Sparks - a PhD-holding research associate at Kansas State University. Adam had the necessary data and tools at hand to generate these two maps - which split the year into two 6-month ranges and then show by month where the average maximum daytime high was between 65 degrees and 75 degrees.
(click maps for larger versions)
Our hope was that by having these maps it would help us decide our route for the year. We know weather is fickle and weather patterns like rain may cause us to deviate from a planned itinerary, but these maps should help the route planning from a macro perspective.
Thanks again Adam!