The last two winters in Hampton Roads have seen their share of cold and snow, but if federal forecasters are right, this winter should be drier and warmer than normal.
The U.S. Winter Outlook for 2016-17 from NOAA’s Climate Prediction Center expects a La Nina ocean-atmosphere cooling phase will form in the Pacific in late fall or early winter, issuing below-average snowfall in the mid-Atlantic and warmer temperatures across the South.
At least, this is the most likely outcome for the season, said Mike Halpert, the center’s deputy director, in a statement last month announcing the forecast.
“It also provides the public with a good reminder that winter is just up ahead and it’s a good time to prepare for typical winter hazards, such as extreme cold and snowstorms,” said Halpert. “Regardless of the outlook, there is always some chance for extreme weather, so prepare now for what might come later this winter.”
Of all weather forecasts, seasonal ones that stretch over months are the hardest to get right, says meteorologist Bill Sammler with the National Weather Service in Wakefield.
Sometimes seasonal predictions are eventually proven wrong. And even when they’re right, he said, there can be a number of different ways of getting there.
“Let’s say you had a warm December and a warm February, but a cold January,” Sammler said. “You could still end up above-normal for the entire winter, even though you had a cold month or cold month and a half.”
So far, November has seen above-average temperatures, although they’re forecast to return to normal this weekend when they sink to the 30s overnight.
NOAA relies on climate science signals to make its winter predictions, including whether a La Nina or El Nino weather pattern forms in the Pacific, the state of atmospheric circulation known as the Arctic Oscillation and conditions in the tropics known as the Madden-Julian oscillation — all of which have far-reaching weather impacts.
By contrast, prognosticators at The Farmers’ Almanac and The Old Farmer’s Almanac issue their own competing seasonal forecasts each year based on sun spots, the tides, the position of the planets and a secret formula, or “set of rules,” developed back in 1818.
This time out, their seasonal predictions diverge.
According to Old Farmer’s, winter along the Atlantic corridor should be pretty much as federal forecasters predict: temperatures averaging about 6 degrees above normal in December and 3 degrees above in January. February temperatures should be normal.
As for precipitation, Old Farmer’s expects below-normal in December and January, but above-normal in February.
Meanwhile, the Farmers’ Almanac forecast is more extreme, predicting “(C)old Man Winter’s” return in the mid-Atlantic and other regions with “exceptionally cold, if not downright frigid weather.”
And, if you want to mark your calendars now, Farmers’ is even “red-flagging” Feb. 16-19 for a “small but intense storm” to develop near the Virginia Capes, dumping a heavy snowstorm and strong winds.
NOAA says it would never project snowstorms this far out because science simply can’t predict such events more than a week in advance.
For more on NOAA’s forecast, go to bit.ly/2e4IXdr.
Dietrich can be reached by phone at 757-247-7892.