We are driving a 36' motorhome and towing a car from Seattle to Peoria in mid March. We have looked at traveling I90 in Washington to I84 through Oregon & Idaho and then catching 93 to Vegas and on to Peoria. We are concerned about weather getting through the mountains in Oregon, Idaho and into Nevada. Is this the best route this time of year or are we better off taking I5 south and then cutting off at Bakersfield taking 40 into Peoria?