This is the snowiest start to winter in Milwaukee and Madison by “virtue of number of days with measurable snowfall,” according to the National Weather Service.As this arctic cold takes aim, 20 states from Colorado to Maine are under winter storm warnings or winter weather advisories.The heaviest snow will be in the Northeast and near the Great Lakes, from the Upper Peninsula of Michigan to western Pennsylvania and into northern New England. Some areas could see up to 1 foot of snow. BREAKING: @AmericanAir Flight AA4125 from @flyfrompti to @fly2ohare slides off runway in Chicago this morning. Passengers tell me everyone is OK, deplaned and on buses to terminal. Video: Joseph Lian from Greensboro. @ABC11_WTVD @ABC #ABC11 pic.twitter.com/rBwyqfVtiU— Andrea Blanford (@AndreaABC11) November 11, 2019 ABC News(NEW YORK) — An early season arctic cold front is barreling through the Midwest Monday morning and is expected to reach the Gulf Coast and the East Coast on Tuesday.Ahead of that cold front was a quick-moving storm which brought accumulating snow to the Midwest and the Rockies, transforming highways into sheets of ice and sending cars veering off roads.In Chicago, the snow has canceled over 600 flights.One plane even slid off the runway due to icy conditions while landing at O’Hare International Airport Monday morning, American Airlines said. No one was hurt, according to the airline. Winter weather advisories & warnings from New Mexico & Colorado into New England. This means snow! Some spots 2-6”, others (in pink) will get lake enhanced 6-12”!!!Raise your hand if you are excited for this hit of snow pic.twitter.com/mom5ITnQWV— Ginger Zee (@Ginger_Zee) November 11, 2019 The coldest morning in the Heartland will be Tuesday morning. Wind chills are forecast to plunge to -4 degrees in Des Moines, -3 degrees in Chicago, 2 degrees in Kansas City and 7 degrees in Memphis.Even Dallas is forecast to reach a wind chill of 15 degrees.The coldest morning for the Southeast and the Northeast will be Wednesday.Wind chills are forecast to fall to -3 degrees in Syracuse, 3 degrees in Boston, 10 degrees in New York City, 24 degrees in New Orleans and 21 degrees in Atlanta.Click here for tips on how to stay safe in the cold. Copyright © 2019, ABC Audio. All rights reserved.