A Rocky Mountain storm shifted into the Midwest, blanketing parts of the Great Lakes with as much as 8 inches of snow that slowed traffic to a crawl. The storm spread snow from Missouri across Illinois, Iowa, Wisconsin, Indiana and Michigan. Rain, sleet and snow pelted northern Arkansas and flurries lingered in Oklahoma, Texas and New Mexico. Snow totals included 8 inches in Milwaukee and 7 inches in Moline, Ill. A Continental Airlines MD-80 jetliner with 75 passengers aboard skidded off a snow-slick runway while landing at Chicago's O'Hare International Airport. Authorities said the mishap closed the runway, but no injuries were reported. The snow fell ahead of an arctic cold front that pushed temperatures far below zero.