It was a slow grind to the warmest January ever in the Twin Cities. Despite a few brief intrusions of cooler air from Canada, the predominate airflow in January was from the Pacific. It was also a relatively snowless month with only 2.3 inches at the Twin Cities International Airport. This made Janaury 2006 the 8th least snowiest January since 1891.
The average temperature for January 2006 was 28.6 degrees. This smashed the 1891-2005 record of 26.6 degrees set in 1944. Unlike 1944, 2006 didn't offer any daily records. On January 25, 1944 the mercury climbed to 58 degrees and that remains the highest temperature ever in January for the Twin Cities. On that day many people walked in their local parks with one passerby noting a four leaf clover in full bloom in Minneapolis. January 1944 was a sunnier than normal month, with little snow on the ground.
Looking back into pioneer records January 2006 fell just short of the warmest January since 1820 in the Twin Cities. January 1846 at Fort Snelling had an average temperature of 28.8 degrees*. It was a cloudy month but very little snow fell. A clue to the lack of snow cover was that prairie fires were observed from the fort on three days late in the month. A January 17, 1846 diary entry from William R. Brown of St. Croix County, mentioned: "Weather continues pleasant. No snow on the ground. I have not seen such a winter in this country, such fine weather and no snow." Despite January 2006 not breaking that 1846 record it was the warmest January in 160 years, or since the Twin Cities was part of Iowa Territory.
January 2006 was also the second time since 1891 that a January has not seen a subzero reading in the Twin Cities. The only other time was 1990. The mercury also probably failed to reach zero in January 1846.
Another aspect of January 2006 was the number of times precipitation fell in liquid form during the month. It either rained or drizzled at the Twin Cities International airport for at least one hour during eight days. Looking at an archive of hourly observations from 1945 to 1995 the average number of days with rain or drizzle is three days.
See this spreadsheet so you can see day by day temperatures for Janaury. The daily maximum and minimum temperatures can also be found here.
So what happens in February after an extremely warm January? Looking at the top ten warmest Januarys in the 1891-2005 record the six were on the mild side with two in the top ten warmest Februarys.
Top ten warmest Januaries and the average temperature of the Februaries that followed.
Ave T Year Ave T
26.6...1944 20.4 (36th warmest)
26.3...1990 23.7 (18th warmest)
25.8...1931 31.9 (1st warmest)
24.6...2002 28.4 (5th warmest)
24.2...1891 13.4 (23rd coldest)
23.1...1933 14.2 (25th coldest)
23.0...1898 20.6 (33rd warmest)
22.4...1958 15.5 (32nd coldest)
22.2...1919 16.4 (38th coldest)
22.0...1921 24.1 (15th warmest)
*Earlier the State Climatology Office reported that the Janaury 1846 average was 28.0, but in checking early typeset records from 1905 it appears that the 28.0 was a typeset error and the average should have been 28.8. This average was calculated by taking the average of the four time daily fixed mean temperatures.