I watched the NBC News last night with more than the usual interest inasmuch as weather instead of politics was the top story. In addition to the heartbreaking tragedies of multiple deaths from tornadoes and drowning in flood waters, the severe blizzard and icing conditions from western NM all the way across the TX Panhandle and into OK were featured. The NM authorities closed I-40 from Albuquerque to the TX line, a distance of some 400 miles. There were snowdrifts over 8' deep in eastern and central NM, record snowfall in Amarillo, TX, and severe icing in OK.
Although there are frequent weather-caused traffic backups along I-70 in CO, short-term closures of I-80 in WY, and the passes along I-90 in MT are closed temporarily from time to time, I doubt there are many times when 400 miles are closed anywhere in the central or northern Rockies, the Sierra, or the Cascades.
As is so often said here, the best plan it to take the shortest route. If serious weather arises, one can normally wait it out for a fairly short time and get back on the road with little muss or fuss.