If 20 below is used as a benchmark for seriously cold weather, then our winters are not as seriously cold as they used to be. During last winter, which certainly seemed like a cold winter, the official thermometer for Fargo-Moorhead at Hector Airport reached a temperature of -20 degrees a total of eight different calendar days, the most since the winter of 2013-14 when there were 10.
The last 20 winters have averaged 4.3 times per winter down to 20 below. During the 20th Century, the average was a bit more than eight days per winter. The record is 39 times in the winter of 1886-87. This trend is observed at all stations with a lengthy period of record, rural and urban, throughout the region. Our winters may be known for their cold, but cold weather is simply not happening as often as it used to.