I'm in Missouri too. We have a problem with extreme cold but a greater problem with heat. Not to mention that it is almost always humid.
After over 30 breeds, Jaerhons (lots of white eggs) get my vote for best breed for both heat and cold.
I now only raise Black Penedesencas. The roosters' huge combs and wattles are a problem right now but the hens never have a problem and the breed is extremely heat hardy.
Otherwise, Ameraucanas, Delaware, New Hampshires, RIRs,Naked Necks/Turkens rose comb Leghorns, rose comb Anconas, rose comb Minorcas, work.
My JGs in all colors did well here.
While I love Welsummers, they're the only breed I've lost to heat back a few years ago when it hovered around 110 for days.