FARGO — The colder months of the year also see the greatest temperature fluctuations. In summer, afternoon temperatures often range from 18 to 30 degrees Celsius. In winter, however, afternoon temperatures can range from -25 to 4 degrees Celsius. The main reason for this is the temperature gradient in the Northern Hemisphere. In the equatorial regions of the earth, temperatures are around 32 degrees Celsius year-round.

Meanwhile, temperatures around the North Pole are near freezing in the summer, while temperatures in the winter are often 50 degrees below zero. This means that the temperature difference between the equator and the pole varies from about 60 degrees in the summer to 140 degrees in the winter. This increased temperature gradient in the winter makes large-scale storm systems more robust and results in much greater weather variety from day to day. This helps explain why our weather typically fluctuates much more regularly as fall progresses.

John Wheeler is chief meteorologist at WDAY, a position he has held since May 1985. Wheeler grew up in the South in Louisiana and Alabama and says his family’s move to the Midwest was important in developing his fascination with weather and climate. Wheeler lived in Wisconsin and Iowa as a teenager. He attended Iowa State University and earned his bachelor’s degree in meteorology in 1984. Wheeler worked at WOI-TV in central Iowa for about a year before moving to Fargo and WDAY.