Above is a chart of the running rainfall total for 2011 (in red) compared to the five driest years on record at Tallahassee (in order: 1954, 1931, 1904, 1921, 1938) and the climatological normal rainfall for any given year.
Through December 5, 2011, Tallahassee has measured just 30.41 inches of rain, which is 25.57 inches below the normal value at this time of year.
The normal rainfall at Tallahassee for an entire year is 59.23". The record driest year is 1954 when just 30.98" of rain fell. The second driest was 1931 when 37.99" of rain fell.
Therefore, a 0.58" rainfall total in the month December will put the record driest year at Tallahassee out of reach for 2011. December rainfall of 0.57" or less would make 2011 the driest year on record. Additionally, Tallahassee would need to measure 7.59" of rainfall in order for 2011 to not go down as one of the top two driest years on record.