Odds are, it's going to be a mild winter in the region
FARGO—The official winter outlook is in, and it has good news for people who dread days of bitter cold and wind chill.
The Climate Prediction Center, a division of the National Oceanic and Atmospheric Administration and a sibling of the National Weather Service, released its outlook Thursday, Oct. 18, placing the North Dakota-Minnesota region in an area indicating a greater than 40 percent chance of warmer-than-average temperatures for December through February.
But this outlook needs some explanation.
Forecasting the weather for an entire winter season is much different than forecasting the weather for tomorrow. A daily forecast is concerned with the location and strength of particular weather features such as storms, fronts, low and high-pressure centers. It is impossible to know where these daily weather features will be over an entire season, so a seasonal outlook is based on large-scale weather features around the world that might influence the storm tracks and the position of the jet stream.
It is also important to understand that this a probabilistic forecast. The region is in the band of 40-50 percent chance of warmer than average. This leaves the remaining 50-60 percent chance as something other than warmer than average, implying a 25-30 percent chance of near-average temperatures and another 25-30 percent chance of colder-than-average temperatures. There is a great deal of uncertainty in predicting weather patterns so far in advance.
The precipitation part of this outlook is even more non-committal and indicates equal chances of wetter-than-average, drier-than-average and near-average precipitation. Note that this equal chance outlook is different than just saying it will be about average. There are simply no good indicators for how much snow or rain the region will get this winter.
The strongest factor in this outlook is the budding El Niño in the Pacific. El Niño causes a warming of the tropical ocean off the west coast of South America, which tends to induce a lot of thunderstorm activity, which can redirect the Jet Stream into a position that favors fewer Arctic air outbreaks into the Northern Plains.
But each winter is unique. There is no such thing as an El Niño winter with a predetermined set of conditions.
In fact, the last time the region had temperatures in the minus 30s was during the El Niño winter of 2009-10. That winter also had heavy snow and a bad spring flood.
Any winter, even a mild one, will have spells of bitter cold and wind chill. Just like even the hardest of winters has a few milder days.
What this outlook says is that the probabilities favor more of the milder days this winter and not as many of the bitter ones.