On October 13, the mercury reached 61 degrees at the Twin Cities International Airport and has stayed below the 60 mark ever since. 2013 will tie with 1880 for having the earliest final 60 degree high temperature. This is for records that begin in 1872. The long term mean is November 6.
Looking at past statistics, there is historically a good chance of seeing a 60 degree temperature sometime in November. For the 1981-2010 normal period there was a 60 degree temperature in 18 of 30 years or 60% of the time. There were also three Decembers that had a temperature of 60 degrees or 10% of the time. In all three of these Decembers there was also at least one 60 degree temperature in November. In recent years, at least one day in November has reached 60 degrees, with the last time a day in November failed to reach 60 was in 2003. The year with the most 60 degree November temperatures was 2001 with 13 days.
Does having an early closure of 60 degree temperatures have any predictive skill for the average temperature for November and the rest of the winter? For November, an early end to the 60 degree temperatures is an almost slam dunk of having a very cold November, with only one of the years finishing warmer than the long term average and one other year being close to average. November 2013 finished a half degree (-.5) below normal.
For December-February there is still a tendency for a colder winter with six out of the ten being cold and four out of ten being warmer winters. Three of the winters are in the top 20 coldest on record, while only one barely makes the top 20 warmest on record.
Top Ten Earliest Last 60-Degree Temperatures and the Average Temperatures that Followed. (Minneapolis-St. Paul Threaded Record 1872-2013) Rank Date last 60 Nov. Avg T rank Dec-Feb Avg T rank ----------------------------------------------------------- 1. 10-13 (1880) 64 1st coldest 23rd coldest 1. 10-13 (2013) 61 67th warmest 9th coldest 2. 10-16 (1988) 63 63rd coldest 65th warmest 3. 10-17 (1873) 63 5th coldest 4th coldest 4. 10-17 (1911) 63 3rd coldest 17th coldest 5. 10-17 (1995) 66 15th coldest 60th coldest 6. 10-18 (1889) 65 34th coldest 36th warmest 7. 10-20 (1928) 64 36 warmest 24th coldest 8. 10-22 (1875) 72 5th(tie) coldest 46th warmest 9. 10-22 (1919) 64 14th coldest 15th coldest 10.10-22 (1959) 63 9th (tie) coldest 19th warmest