Polar vortex to usher widespread cold, snow chances into US during mid-January(VIDEO)
SOURCE abcnews.go.com
During the middle of January, a brief shift of the polar vortex will direct waves of cold air southward and could raise the chance of snow in the central and eastern United States that have experienced little cold or snow thus far this season.
The pattern of cold air coming and going will continue be a theme for January.
Following the arctic blast around the Great Lakes and Northeast states from Sunday to Tuesday, temperatures will trend to above-average levels over much of the Central and Eastern states for a several-day stint.
The mild air reached a peak over the northern Plains on Friday, and will peak the Midwest on Saturday and the East on Sunday.
Temperatures will peak in the lower 40s in Chicago, near 60 in Washington, D.C., and the 50s in Atlanta. However, the warmup will be of short duration.
Arctic express poised to ramp up
According to AccuWeather Chief Long Range Meteorologist Paul Pastelok, "Blasts of cold air will sweep in over much of the Central and Eastern states next week [Jan. 10-16]."
The polar vortex will shift southward across Canada and set up near Hudson Bay for a several-day stint during the second full week of January.
Even though this setup is not uncommon for January, it will deliver a widespread shock following record warmth during December.
While the core of the cold air with the arctic outbreak during the first few days of January focused on the Northeast, the outbreak next week will focus on the Plains and Midwest. However, some significant cold air, relative to this winter will reach the Atlantic coast and the South.
The first wave of the frigid air will sweep across the Plains and Midwest this weekend. NFL fans heading to the game at Minneapolis on Sunday should be prepared for one of the coldest playoff games on record with AccuWeather RealFeel® Temperatures well below zero.
The first wave will reach the East in modified form during Monday into Tuesday.
Additional waves of frigid air will rotate around the polar vortex like a giant wheel with each pushing progressively colder air farther east and south.
"A blast will sweep quickly southeastward around Jan. 13, followed by another blast around Jan. 16," Pastelok said.
Even though the air will continue to moderate as it moves along this path, there is still the likelihood of the lowest temperatures of the season so far from the northern Rockies and Plains to the Midwest, and South during the middle days of the month.
During the second week of January, highs will be within a few degrees of zero F over the northern Plains and Upper Midwest. Lows will be well below zero in the region.
With the mid-month cold blast, several days with highs in the teens are likely in Chicago. High temperatures on one or more days in New York City could be held to the 20s. Temperatures could struggle to climb past the lower 40s as far south as Atlanta with hard freezes at night across the interior South. However, freezes are likely to stop short of the Florida Peninsula during the mid-month cold outbreak.
Cold to bring opportunities for snow
As the first wave of cold air begins to push southward and eastward, a storm will bring the potential for accumulating snow over part of the Midwest on Sunday.
The same storm on Sunday will bring rain along the Atlantic Seaboard. However, the storm could end as snow or snow showers over parts of the Appalachians.
"During the second full week of January, the pattern will evolve where Alberta clipper storms sweep southeastward around the polar vortex," Pastelok said.
These fast-moving, cold storms have the potential to bring quick light to moderate snowfall over parts of the Plains, the Great Lakes and the central and northern Appalachians.
Parts of the mid-Atlantic coast could get their first coating of snow during the second week of January.
If one of these systems was to strengthen upon nearing the Atlantic coast, then there could be significant snow in the Interstate-95 corridor of the mid-Atlantic. The first such event could develop later Tuesday into Wednesday. However, the odds are greater for a few inches of snow in portions of New England.
Regardless of the extent of storms bringing general snowfall, bands of heavy lake-effect snow will develop as the cold air streams across the Midwest during the middle days of the month. The pattern could unload a few feet of snow and produce local blizzard conditions, where lake-effect bands persist.
Polar vortex forecast to retreat northward past mid-month
"Indications are the polar vortex will retreat northward beyond Jan. 16," Pastelok said. "There is a significant chance that milder air from the Pacific will mix in from west to east beginning during the third week of January."
While the Pacific air would allow temperatures to trend to near or above average in many areas, the recovery would likely stop well short of record warmth.
"Because of a buildup of snowcover over eastern Canada and big storms moving offshore, cold air may continue to periodically invade part of the Northeast, especially New England, during the latter part of January," Pastelok said.
Despite the forecast retreat of arctic air during the second half of the month, the air may remain cold enough for storms that come along to bring snow in parts of the Central, Southern and Northeastern states.
http://www.accuweather.com/en/weather-news/polar-vortex-to-usher-widespre/54599939
kcontents
"from past to future"
daily construction news
conpaper