The cold weather this week made me wonder how rare such cold snaps are around here. I found daily high and low temperatures going back to 1910 — nearly 100 years of data. Yesterday’s low was 5 ºF. During the past hundred years, the daily low has been 5ºF or below on 91 occasions. So it happens slightly less often than once a year. That’s not too bad.
The figure below shows the average annual temperature from 1910 through 2007. Notice any trends? I don’t. Linear regression says slope of average temperature vs. year is negative (-0.004734), but not statistically significant (p=0.264).