The shortest route from Mokena where you live is the one shown by Google maps through St. Louis, OKC, ABQ and down. But as previously suggested heading further south could be better weather and temp wise - it will add a lot of miles to your trip though. The trouble is you almost have to drop all the way down to I-10 to get below the freeze line and that's really far.
Phoenix is a SUPER popular winter destination and can be difficult to find reservations for longer stays. We go to Tucson every winter for a month and reservations a year in advance are required for that length of stay. But this year may not be nearly as crowded due to Covid and US boarder closings.
Southern Arizona in Jan/Feb is really nice. 70 degree days and 45 degree nights and no humidity. Though you can see cold snaps come through every few weeks.
That is pretty much exactly what we did and it was a good ride. They said when in Az 17 has less elevation so we took that. However the last hill was a big one. It was long and slow.
There is a statewide mask order in Texas for the vast majority of locations and has been since mid-summer. Though some ignore it. The majority of businesses do however enforce it. Especially the grocery stores and restaurants.
This was our first madden voyage with our Winey and we stuck to stopping at camp grounds and brought enough food to cook our own meals. Except the last night because of the break downs I ordered a pizza. Its been almost two weeks and were doing fine
I17 has a long pull or 2 to deal with. 1 if I remember right is 3-4 miles, other is around 7 followed by a long steep downhill when going north. No big thing just that you will probably be in the right lane with hazards on going slow! Also be careful at time of day, posted elk crossings in the areas, so there may also be deer?
I-17 has a hard pull getting into Green Valley, and a second one pulling up to Flagstaff. After that, it is all flat land to Illinois but the hill at the continental divide in New Mexico. Fortunately it is all down hill from there.
I am planning on making the trip from AZ to Illinois the day after Christmas. Not really looking forward to the cold.
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-- I must be the last optimist on the planet
2018 Winnebago Intent 31P
Roadmaster anti-sway bar Front/Rear, Safe-T-Plus, SumoSprings-Front/Rear