The first half of autumn is nearly complete and the past 6 weeks have been one of the warmest starts of fall since 1881. This year continues the trend of milder autumns that this area has recorded in recent years. This trend of warmer temperatures this time of year has increased the average temperature for September, October and November by 1 degree. The average autumn temperature from 1971-2000 was 43.5 degrees and our current 30-year average from 1981-2010 is 44.5 degrees.
Some of you may take this as a sure sign of global warming, except, the average fall temperatures from 1931 through 1970 was also 44.5 degrees. You see, a series of cool falls in the 1970s and 1980s caused an over decrease in the average and our recent stretch of mild autumns has help increase our autumn temperatures closer to the long-term average after a brief period of cooler conditions.
This is yet another example of how climatic conditions subtly change over time.