Wisconsin to Nevada, middle of February
We are leaving Wisconsin on February 16th and hoping to be in Nevada on the evening of the 17th. Four drivers and one night stopping along the way. Which route would be best - Hwy 80 or going the southern route. This arrival date is not set in stone depending on weather conditions. We would prefer I80 but are worried about snow storms going through that area. We would of course keep ourselves posted on weather conditions. We have traveled this route many times in the summer but never during winter.
Two Options, But Not Two Days
You basically have a choice between two routes, both of which are essentially all-Interstate and both of which will take a minimum of three to four days to complete safely since they're both about 2000 miles long. There is simply no way, no matter how many drivers you have, to drive 2000 miles in two days.
The 'northern' route is the 'I-80' route you referred to, and goes to Las Vegas first. Take I-43/I-39 south out of the Milwaukee area to I-88 near Rochelle IL. Note that I-88 is toll in portions. Follow that to I-80 at the Quad Cities and follow that to western Nebraska, Take the I-76 cutoff to Denver and I-80 over the Rockies to I-15 south in Utah.
The 'southern' route is slightly longer and goes to Laughlin first. Take I-43/I-39 south out of the Milwaukee area to Normal IL, then I-55 to St. Louis, I-44 to Oklahoma City, and I-40 to Needles CA, finishing up on AZ-95 north to Laughlin.
Note that neither route is guaranteed to see better weather than the other. I-40, while father south and relatively flat, reaches elevations near 8,000 feet across much of northern Arizona and can - and does - see snow, ice, high winds, and other nasty weather.
AZBuck