January 19, 2014 saw a new record high of 66F in Lincoln, NE breaking the old record of 65F set over 100 years ago in 1895.
This raises an interesting question.... how common is it to have temperatures this warm in January? And is there any trend in the frequency of these warm January temperatures?
Lincoln daily temperature data extend from January 1887 to January 2014. The following graph shows the warmest temperature during each January during this 128 year time period.
The 66F observed on January 19, 2014 is not the warmest recorded January temperature in Lincoln, NE. The warmest January temperature observed in Lincoln during this time period is 73F set on January 10,1990.
There were 12 months of January which hit 66F or higher since 1981 (34 years) however,
only 9 months of January hit 66F or higher during the period 1887-1980 (94 years).
1981-2014 Percent of Januaries that saw at least 66F or higher = 12/34 = 35.3 %
1887-1980 Percent of Januaries that saw at least 66F or higher = 9/94 = 9.6%
Clearly the probability of having a January temperature of 66F or higher is greater during the more recent time period.
Breaking this down by 20 year time periods for the highest temperature observed in each January:
20 Years Frequency 66F or Higher