January Outlook Update: Much Colder in the Northwest, Northern Plains as the Gulf Coast Remains Mild

Brian Donegan and Linda Lam
Published: December 28,2016

Pictured here is the January 2017 temperature outlook. Areas not shaded have an equal chance of above- or below-average temperatures.
(The Weather Company, an IBM Business)

January 2017 is now expected to be much colder than average from the Pacific Northwest into the upper Midwest, while parts of the Gulf Coast states will see a mild January, according to an outlook released Wednesday by The Weather Company, an IBM Business.
"There is high confidence for a stretch of notably cold weather during the first couple of weeks of the month, with similar, but slightly earlier, timing as in December" said Dr. Todd Crawford, chief meteorologist with The Weather Company.
The expected trend of a cold January in the Northwest, northern Plains and parts of the upper Midwest continues what we've seen in December.
(MORE: Winter Storm Central)
Colder than average temperatures have gripped much of the northern tier, especially the Pacific Northwest. Snow and ice have already occurred on a couple of occasions this December in the lower elevations of the Pacific Northwest due to the cold temperatures.
The East is expected to continue to experience periods of colder temperatures, along with periodic warm ups and a overall milder back-half of January.

Average January Highs

One of the biggest factors for the temperature pattern expected in January is La Niña. La Niña is the periodic cooling of eastern Pacific equatorial water, which can exert some influence on the atmospheric pattern, particularly in the colder months.
La Niña usually correlates with colder-than-average temperatures in the northern and western U.S with warmer-than-average temperatures in the southern and eastern U.S, which is overall what is expected in January.
(MORE: La Niña is Expected to Last Through Winter | Winter Storm Central)
In fact, the best chance for above-average temperatures in January will be toward the Gulf Coast and in Florida, which is fairly typical for a La Niña winter.

Late-Winter Outlook: January-March

Colder-than-average temperatures are expected to continue in the Northwest into February and March, while above-average temperatures persist and spread across the South.
Elsewhere, a large swath of the Midwest and Northeast is forecast to see temperatures generally near average for the January-March period.

Pictured here is the January-March 2017 temperature outlook. Areas not shaded have an equal chance of above- or below-average temperatures.
(The Weather Company, an IBM Business)

A possible wild card in the forecast is the polar vortex, whether or not it will weaken again this winter and, if so, when.
(MAPS: 10-day National High/Low Forecasts)
"If a significant stratospheric disruption occurs, it would most likely not have significant impacts until February," Crawford added.
When the polar vortex is weakened or elongated, it can help bring arctic cold into portions of North America and Europe.
(MORE: What is the Polar Vortex?)

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