I checked for Nov 25 and at the northern end of the Ozark Mountains (Springfield MO.) the average high is 52º, and the low is 31º.

Just below the Ozarks is the Ouachita National Forest, it's about 58º & 40º there.

Best I could figure for Zion is probably around 55º and 32º.

A 5-7 day hiking trip in late November just about anywhere in mainland U.S. has the potential for some pretty nasty weather. You might look around San Diego or Florida and see what they have to offer. They're about the only places I can think of that'd be that warm then.

I don't know much about backpacking in Central and South America.