concerned about winter road conditions when trying to decide best route from Chicago to Los Angeles. Heading out in a week and a half and would like to see grand Canyon or santa Fe, depending on route we choose. How is I70 thru rockies west of denver? Is hwy 191 in Utah a good road in the winter to cut south off of I70? From hwy 191 we could tie into 160, head west to 89 in order to take 64 into the grand canyon. Is this route doable in the winter??? Another route would be to get to Denver and if weather is bad thru pass on I70, we could head south on 25 thru Santa Fe and Albuquerque and then hook into 40 and head west to CA. Is this also a doable route in the winter?? thanks!