Okay, so, weather summary from the NOAA graphical CONUS view.
In terms of snow/mix, it looks like you're going to have a window to get through Texas panhandle and NM that's from mid-day tomorrow (Saturday) through Sunday day. There is some snow now through mid-day tomorrow, then it clears, but then by Sunday night a new bunch comes. It's a skinny window.
Temps are going to be cold at night. The stretch from Amarillo, TX to Kingman, AZ on I-40 will be quite cold at night (that's like an 11-hour drive across). But that's the most direct route, so you could either have one
very cold night, one plugged in very cold night, or one looong stretch to get across it. There is a slightly low/warm point in the middle of that around the Winslow Walmart but even that will be 9ºF on Saturday night!
(21ºF on Sunday night but that's close to when snow comes back).
On I-10 it will also be cold, but less cold and the band of cold is narrower. If you are going to cut down to I-10, the most direct is to start down around Memphis, TN -- but then you go through Dallas/Ft. Worth (not all that fun), but maybe not so bad on a Saturday? If you do head across Texas that way note there are a few long stretches without gas. Nothing the Chinook can't handle just be aware.
Or you can stick it out on I-40 Amarillo and then go down on I-27. More of a right angle corner. If you do stay on I-40 to Amarillo then be wary about "cutting across" to I-10 on anything that looks shorter than I-27 to I-10. There be mountains there in southeastern NM!
So in summary from what I can see now:
1) Snowy patch on I-40 centered in NM will dissipate mid-day Saturday and stay clear through late Sunday (maybe early Monday morning?). Overnight lows will be brutal pretty much the whole way from Albuquerque to just west of Kingman -- that's an 11-hour drive or so if you want to blast through it.
2) Same snowy patch (albeit a bit narrower) will affect I-10 through Sunday mid-day, then be clear until mid-day Monday (then more snow comes). Lows will still be unseasonably cold, but not as cold as I-40 and the "cold band" is narrower (shorter area of high altitude).
I'll post screen shots here and into the next reply. First, the "weather" tab that shows systems. I'll start late tonight so you can see the progression.
Tonight (Saturday 2a.m. MST):
Saturday afternoon, 2 p.m. MST
Sunday morning (8 a.m. MST)
Sunday night (11 p.m. MST)
Continued...