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On this date in 1989 record cold swept in the day after Thanksgiving to begin the coldest spell of weather on modern records. St. Johnsbury set a record at 6 below zero, while Concord, NH was close behind with -5. The coldest readings were nestled into the upper reaches of the Connecticut Valley, with First Connecticut Lake, NH at 10 below zero. The cold lasted all of December, the coldest month on modern records.