Midwest U.S. in brutal grip of colder-than-Antarctica deep freeze

Frozen Arctic winds brought record-low temperatures across much of the U.S. Midwest on Wednesday, unnerving residents accustomed to brutal winters and keeping them huddled indoors as offices closed and even mail carriers halted their rounds. Classes were canceled Wednesday and Thursday in many cities, including Chicago, home of the nation's third-largest school system, and police warned of the risk of accidents on icy highways. In a rare move, the U.S. Postal Service appeared to temporarily set aside its credo that "neither snow nor rain ... nor gloom of night" would stop its work: it halted deliveries from parts of the Dakotas through Ohio.