Brutal cold shuts schools, delays travel in U.S. Midwest CHICAGO (Reuters) - Bitter cold and high winds from the arctic pushed wind chills to dangerous levels across the U.S. upper Midwest on Monday, forcing officials to close schools and slowing public transit and river traffic. A winter storm system is forecast to move through the U.S. South on Tuesday, bringing snow, freezing rain and high winds as bitter cold temperatures continue in the Midwest, according to the National Weather Service. Chicago, Minneapolis, Milwaukee and other parts of the upper Midwest are forecast to have a second consecutive day of subzero highs on Tuesday, while most of the Northeast will see highs in the single digits and teens on Tuesday and Wednesday, according to Accuweather.com. The weather will force schools to close on Tuesday in New Orleans, Minneapolis, Chicago and Milwaukee, and government offices in Indianapolis, Galveston and Milwaukee County will also be closed. Tulane University in New Orleans, University of Michigan in Ann Arbor, and The Ohio State University in Columbus have canceled classes ahead of Tuesday's storm. Amtrak has also canceled a number of train routes in and out of Chicago on Tuesday because of the frigid weather conditions. For much of the South, a winter storm warning will be in effect on Tuesday, including in New Orleans where winds will gust and ice and snow will accumulate on the roads, making travel hazardous, according to the National Weather Service. Heavy snow was expected beginning on Tuesday across eastern North Carolina, while coastal South Carolina will get rare ice accumulation with some snow and temperatures will be below freezing on Tuesday and Wednesday, the National Weather Service predicts. The frigid temperatures also were causing ice to accumulate on the Mississippi and Illinois rivers, slowing the movement of grain barges to the U.S. Gulf, according to Drew Lerner, a meteorologist at World Weather Inc. In Alaska, the roughly 4,000 residents of Valdez remained cut off to road traffic from the rest of the state Monday after weekend avalanches blocked the road to the coastal town, officials said. Reporting by Mary Wisniewski; Additional reporting by Brendan O'Brien in Milwaukee, Julie Ingwersen in Chicago, David Bailey in Minneapolis, Kim Palmer in Cleveland, Colleen Jenkins in Winston-Salem, N.C., Harriet McLeod in Charleston, S.C., and Karen Brooks in Austin; Editing by Steve Orlofsky and Ken Wills