Chris Dolce
Temperatures this winter in the United States could have the signature of El Niño's influence, according to an outlook released Saturday by The Weather Company, an IBM Business, and Atmospheric G2.
El Niño's influence shows up in the overall three-month winter outlook: A strong El Niño is favored this winter, which is typically associated with warmer-than-average conditions in much of the northern U.S. It also means parts of the southern U.S. usually see temperatures somewhat below-average in winter.
That temperature pattern is generally the theme of this winter's outlook in the map below.
(MORE: NOAA's October Update On El Niño)
The temperature pattern that's expected to dominate for the entire three-month period from December through February.Keep in mind this outlook is an overall three-month trend. Therefore, we will likely see periods that are warmer or colder in each respective region of the country when compared to what is shown above.
With that in mind, let's dig into the month-by-month details and follow up with some important factors that could change this outlook.
Winter could begin much warmer than average from the Northern Plains to the Great Lakes and Northeast: Those in the northern U.S. wishing for a cold December to set the mood for the holiday season might be out of luck this year. Cities like Minneapolis, Chicago, Boston and New York City are all currently favored to have temperatures the farthest above average.
The southern tier of the U.S. should see temperatures pretty close to what's typical.
Temperature outlook for December.The southern U.S. could skew somewhat colder than average to start the new year: A hallmark of El Niño is cool, wet conditions in parts of the southern states in the heart of winter, and that's what the outlook is showing from the Southern Plains to Georgia and the Carolinas. It's not a guarantee, but that combination of ingredients could increase the chances of snow and ice in portions of this region.
Parts of the Northwest and Northeast have the highest odds for above-average temperatures in January.
(MORE: How El Niño Could Impact Winter Snowfall)
Temperature outlook for January.Winter's final full month could feature a colder East, warmer West split: In February, the core of the warmest temperatures compared to average could be in the Northwest and northern Rockies.
The best chance for colder-than-average temperatures might be from the Southeast to the mid-Atlantic.
Temperature outlook for February.These Factors Could Change The Winter Forecast
1. How much of an atmospheric response will there be to El Niño's warm Pacific waters?: That atmospheric response in the tropical Pacific, so far, has been muted for this time of year when compared other historically strong El Niño winters, according to Dr. Todd Crawford, Vice President of Meteorology at Atmospheric G2.
The conditions in the atmosphere right now resemble the 2009-10 El Niño, which was notably colder in the central and eastern U.S. So trends will be watched in the coming weeks and months to see exactly how much influence El Niño has on weather patterns this winter, and therefore, whether the outlook could trend colder for some.
2. Will the polar vortex weaken later in winter? When the polar vortex weakens, the cold air typically trapped in the Arctic can spill out into parts of Canada, the U.S., Asia and Europe because the jet stream becomes more blocked with sharp, southward meanders, sending more persistent cold air southward toward the mid-latitudes.
Crawford said there is a very good chance the polar vortex could weaken in mid-winter, which means there are colder risks in the U.S. during the back half of winter.
Example of a weak polar vortex in winter.3. Will the recent spike in global warmth influence the magnitude of warmer and colder periods? Earth was on pace to have its warmest year on record as of the end of the September.
"The extra burst of global warmth that has appeared in 2023 will result in an upward offset to temperatures, i.e., warm periods will be even warmer than usual and cold periods will be less cold than usual," said Crawford.
Chris Dolce has been a senior meteorologist with weather.com for over 10 years after beginning his career with The Weather Channel in the early 2000s.
The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.
The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.
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