It could be a warm winter, but that doesn’t mean it won’t snow



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Winter might well have been on the minds of many Mbadachusetts residents Thursday, as the weather abruptly turned cold, with a biting wind that made you wish you’d worn a heavier coat.

So how bad is it going to be?

Federal forecasters say a warmer-than-normal winter could be in store for New England. But the jury is out on whether it will be wetter than normal. And, as far as snow goes, that can’t be predicted so far in advance.

With impeccable timing, the National Oceanic and Atmospheric Administration’s Climate Prediction Center on Thursday issued its US Winter Outlook for December through February.

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The NOAA forecasts estimate the likelihood that temperatures and precipitation will be above, near, or below average for the United States.

The forecast predicted a warmer-than-normal winter for the northern and western three-quarters of the nation, including New England.

The southeastern quadrant of the country could go either warmer or cooler on temperature, said Mike Halpert, deputy director of the Climate Prediction Center.

No place in the United States is seen as more likely to be colder than normal, Halpert said.

Overall, this winter looks a lot like the last few, Halpert said.

‘‘The country, as a whole, has been quite mild since 2014-2015,’’ Halpert said.

Winter weather expert Judah Cohen, of the private company Atmospheric and Environmental Research, uses different indicators to predict winter for the National Science Foundation. He also forecast a warm winter, heavily based on weak snowfall in Siberia.

In terms of precipitation, it’s a toss-up. New England has an equal chance of above- or below-average precipitation.

The forecasters said the southern third of the United States and much of the East Coast, up to New England, could be hunkering down for a wetter-than-normal winter. The chances are highest in southeastern Georgia and much of northern and central Florida.

But New England and much of the rest of the nation are expected to have an equal chance of having a wetter-than-normal winter.

Hawaii, Montana, Michigan, parts of Idaho, Wisconsin, northern Illinois, Indiana, and Ohio are forecast to be drier than normal, with the biggest likelihood in Hawaii, Montana, and Michigan.

Forecasters say it’s hard to predict snowfall very far in advance because cold temperatures and precipitation can combine to make snow even in a warmer than average winter.

“Snow forecasts are generally not predictable more than a week in advance. Even during a warmer-than-average winter, periods of cold temperatures and snowfall are still likely to occur,” the center said in a statement.

Halpert said the biggest factor in the forecast is a probable El Niño, the natural warming of parts of the central Pacific Ocean that influences weather worldwide.

The El Niño hasn’t quite formed yet, but it’s almost warm enough. Meteorologists predict there’s a 75 percent chance it’ll be around this winter. But it will be weak, not strong like the El Niño that helped lead to the record warm 2015-2016 winter, Halpert said.

“We expect El Niño to be in place in late fall to early winter,” Halpert said in a statement. “Although a weak El Niño is expected, it may still influence the winter season by bringing wetter conditions across the southern United States, and warmer, drier conditions to parts of the North.”

Other large-scale patterns that can affect winter weather include the Arctic Oscillation, which can send arctic air mbades into the South, and the Madden-Julian Oscillation, which can cause heavy precipitation on the West Coast, but they are “challenging to predict on a seasonal time scale,” the center said.

While El Niño is the biggest factor in the forecast, long-term warming from human-caused climate change is a factor, too, Halpert said.

‘‘All things being equal, the slight kick we get out of the climate signal does tilt things toward the warm side,’’ Halpert said.

It was the fourth hottest September for the globe, and it has been the fourth warmest year through September, according to NOAA.

But climate change is not enough to outweigh other factors if they push toward cold.

‘‘Even on a warming planet,’’ Halpert said, ‘‘it doesn’t mean winter goes away and it’s never cold again.’’

Material from The Associated Press was used in this report.

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