Weather Talk: It doesn't get to zero and 20 below like it used to
Winter is slowly approaching and that means cold weather, obviously. But "cold" is a relative term.
Two benchmark temperatures are zero degrees and 20 below zero. Over the entire period of record (dating back to 1881), the frequency of these two benchmark temperatures has been declining.
During the first 30 years of record (1881-1910), zero happened about 60 nights a year and 20 below about 15 nights a year. Over the last 30 years (1987-2016), zero has happened only about 40 nights a year and 20 below about six times a year, on average.
The greatest number of zero degree recordings in a winter was 95 in 1883-84. The least number was 15 in 1930-31. The greatest number of 20 below zero recordings is 39 in 1886-87.
There have been 10 winters in which the temperature never reached 20 below. Five of those winters have been in the last 23 years.