Minnesota is in the grips of a historic warm streak, now standing at 18 months in many locations, including the Twin Cities.
February 2017 started off relatively tame, with the usual flip-flopping between warm and cold conditions for the first nine days. The 10th, however, kicked off a 2-week spell of significantly warm weather, including a six-day run between the 17th and 22nd that broke numerous records. In the Twin Cities, daily temperatures were above averages on 23 of 28 days, and the average monthly temperature has now been above the 1981-2010 normal for 18 months in a row.
As a month, February 2017 was among the warmest on record across the state. It ranked in the top-10 at Duluth, the Twin Cities, Rochester, and St. Cloud--where it was 3rd warmest since 1895.
The Twin Cities have not recorded average monthly temperatures that were below 1981-2010 normals since August 2015. This is the longest above-average monthly temperature streak of any kind on record in the Twin Cities, though it is worth noting that the "normals" refresh every 10 years, and procedures for calculating them have changed over time. As of this writing, only five months out of the last 33 (back to June 2014) have been below normal in the Twin Cities. The second longest streak on record was 16 months, from June 2011 through September 2012.
This climatological decade (beginning January 2011), over 70% of months have been above the 1981-2010 normals. In the previous climatological decade, 68% of months were above the 1971-2000 normals, and the Twin Cities has not had a string of 10 or more cool months since 1964-65. Indeed, the whole of Minnesota has been warming rapidly since about 1970, making above-normal temperatures more likely than below-normal ones, even as the baseline values are updated to reflect the warmer conditions.
Twin Cities Average Monthly Temperatures
Avg Dept. from Month Year Temp 1981-2010 Normal --------------------------------------------- September 2015 67.9 + 5.9 October 2015 52.1 + 3.2 November 2015 41.3 + 7.6 December 2015 30.2 +10.5 January 2016 17.6 + 2.0 February 2016 24.9 + 4.0 March 2016 41.3 + 8.5 April 2016 48.1 + 0.6 May 2016 61.3 + 2.2 June 2016 71.3 + 2.4 July 2016 75.2 + 1.4 August 2016 73.4 + 2.2 September 2016 66.1 + 4.1 October 2016 52.9 + 4.0 November 2016 44.1 +10.4 December 2016 20.9 + 1.2 January 2017 20.9 + 5.3 February 2017 31.2 +10.3