Winter will take a turn toward slightly colder-than-average temperatures in 2021, but it may not be wetter, according to meteorologist Daryl Ritchison.
Ritchison, director of the North Dakota Agricultural Weather Network, gave his long-term weather outlook during a Thursday, Dec. 10, session of the annual Prairie Grains conference, this year held virtually.
Though some forecasters have predicted the winter of 2021 will be both colder and snowier because of a weather pattern called La Nina, Ritchison doesn’t concur. He says that a few excessively snowy winters during years when there were La Ninas skewed the information that weather experts used to make this winter’s forecast.
Rather than being wetter this winter, Ritchison forecasts that the dry pattern that began in 2020 will continue into the winter of 2021 and beyond, and snowfall in North Dakota will be about average or slightly below.
Average annual snowfall in Grand Forks is 47.8 inches, according to Weather Atlas. January, with a total of 11.2 inches of precipitation, on average, is the snowiest month in Grand Forks.
Long-term weather records, which date back to the 1700s, indicate consecutive dry years typically came after wet cycles, Ritchison said. For example, in recent history, a wet cycle from 1901 to 1909 was followed by dry conditions from 1929 to 1941.
Meanwhile, peaks in the level of the Great Lakes in the 1920s, 1950s and early 1980s, were followed by drought years, Ritchison said.
“I look at where we were at when there were similar conditions and what happened then. When I’m forecasting long range, I put the pieces of the puzzle together and see where they fit,” he said.
“I think there are many reasons to see why 2021 will be dry,” said Ritchison, explaining that thunderstorms still might drop heavy rains in some areas, but the overall weather pattern will be drier than it has been.
This year has been one of the driest on record in North Dakota, Ritchison said. While many areas of the state still have good subsoil moisture, the top soil is another story.
“It’s absolutely bone dry,” he said.
Based on history, Ritchison is not surprised that 2019, which was excessively wet, was followed by a dry year in 2020.
“In looking back at history, we haven't had two exceptionally wet years in a row except in Bismarck,” Ritchison, noting that in the state’s capital city, where weather records go back to the 1850s, there were three straight years of excessive precipitation.
The wet weather in fall 2019, which saturated fields so much that North Dakota farmers couldn’t harvest thousands of acres of crops, actually benefited them in 2020, Ritchison said.
“One of the things that ended up saving us is the wet fall of 2019,” he said.
Ritchison says that 2019 was the last year of the wet cycle that began in 1993. The average wet cycle lasts 20 to 25 years, he said, noting that during that there may be a few anomalies.
“North Dakota is in the slow process of transitioning from wet cycles and moving into drier,” said Richison, noting that drier weather doesn’t mean there will be a drought, but that the pattern will return to more normal. “Once the wet cycle ends, you’ll probably go back to how your grandfather and father farmed for decades."