CHICAGO (AP) -- A huge storm that stretched from Texas to the Great Lakes blanketed the nation's midsection with snow, tying up air travel and making roads treacherous, and headed for the Northeast on Friday.

Five inches of snow was reported at Chicago's Midway Airport by early Friday and more was expected to begin around rush hour. More than 600 flights were canceled Thursday at O'Hare International Airport, where low visibility continued to be a problem Friday, officials said.

Between eight to 12 inches of snow was forecast for the Chicago area by Friday afternoon.

"It looks like this morning's rush hour is going to be really impacted," National Weather Service meteorologist Paul Merzlock said. "With what's going to be coming down at the rate it'll be coming down, all the roads are going to be snow packed and snow covered."

Elsewhere, Indianapolis received less than 2 inches of snow overnight, despite predictions for much more. But the National Weather Service said northern Indiana could get up to a foot of snow. Fort Wayne had received 4 inches by early Friday.

Hundreds of schools in Michigan canceled class Friday in anticipation of the storm, which was expected to drop as many as 13 inches of snow in the southeastern portion of the state. Up to 4 inches had fallen by early Friday.

Billowing snow in the Texas Panhandle caused a 40-car pileup on Interstate 40 on Thursday that killed at least person. Three other deaths were blamed on the storm, two in Texas and one in Oklahoma.

The storm pounded areas of the Midwest still rebounding from storms earlier in the week that spawned a mix of snow, brutal cold, tornadoes and hail.

The system was expected to move into the Northeast later Friday, bringing with it a wintry mix of snow, sleet and freezing rain.

Severe weather wasn't expected to let up anytime soon in Idaho, which has been besieged by snow in recent days.

National Weather Service meteorologist John Livingston said a snowstorm was expected to blow through on Saturday and Sunday, with cold predicted to stretch at least through the middle of next week.

Officials in Kootenai County in northern Idaho declared a state of emergency Thursday as roofs collapsed, roads became impassable and senior citizens were stranded because of the repeated snowstorms.

"You can only stack the snow so high, and we're running out of places to put it," said Rick Carrie, county commissioner.

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