A confluence of weather patterns may be setting the stage for a colder-than-usual winter in the eastern United States.
But it’s tough to tell what that could mean for exact temperatures and potential snowfall, said Wayne Albright, a meteorologist with the National Weather Service in Wakefield.
Some major weather phenomena over the Pacific and the North Atlantic – called oscillations – are projected to maintain negative pressures over the next several weeks. Negative pressures mean colder air from the Arctic could spill down into the lower 48 states, similar to the Polar Vortex phenomenon in early 2014.
However, that won’t happen immediately and if it does, the lower temperatures would be averaged out over the winter, Albright said. And many other variables could still steer the season’s temperatures one way or the other.
“Right now, we should be colder if you look at” those two oscillations, Albright said. He noted Virginia temperatures have been in the mid-60’s for much of the last few weeks.
Factors like the North Atlantic Oscillation become stronger drivers of the weather and temperature as the winter progresses, Albright said, with their impact peaking in March.
“The tropics drive the mid-latitudes, where we are, just as much as the Arctic. That’s part of the reason you can’t get a 30-day exact forecast,” he said. “They fight each other.
“The weather is a war all the time.”
The new projections are a departure from those released by the National Weather Service in October, which said a warmer winter was more likely than a cold one based on influences from patterns like El Niño and La Niña.
Albright added that the prediction for a chillier winter doesn’t mean the East Coast will get a white Christmas.
“You’re going to have two primary drivers that are going to lean toward colder. That doesn’t necessarily mean it’s going to snow,” he said.
“Snow around here is a lot trickier than that.”
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