I've tried I90 through Idaho (hit Snow)to I15 and down. I84 to I15, hit snow east of Twin Falls to I15 twice and snow at Cedar City, Utah twice. My preferred route from Grand Forks, Canada, is 395 to I84 to Twin Falls. Hwy 93 to Ely. Hwy 6 west to Hwy 318 south to where it meets Hwy 93 at Ash springs, Hwy 93 to I15 and your in Las Vegas. In five trips I had compact over the pass east of Pendleton twice, once each way. I leave the middle of Jan. and watch the 10 day forecast.