Across the Corn Belt, a cold front crossing the upper Midwest separates record-setting warmth from sharply colder conditions.  On Monday, all-time February and winter records were established in Midwestern locations such as Moline, Illinois (76°F); Dubuque, Iowa (72°F); and Rochester, Minnesota (69°F).  Early Tuesday, however, temperatures have fallen below 10°F in much of North Dakota.  In the middle Mississippi Valley, a final day of record-setting warmth will again push maximum temperatures to 80°F or higher. 

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