A shift in the polar vortex will allow Old Man Winter to deliver some of the coldest air of the season so far to parts of the northeastern United States from Friday through Saturday.
The extreme cold coming directly from the Arctic will produce extraordinary AccuWeather RealFeel® Temperatures and challenge several long-standing record-low temperatures.
The polar vortex, which is a storm at the jet stream level of the atmosphere, has kept frigid air pent up above the Arctic Circle for much of the winter. When the polar vortex remains strong as it has been, frigid air cannot escape the Arctic. However, in recent days the polar vortex has weakened and stretched just enough to allow the bitterly cold air to move southward across North America.
“This time, a small, fast-moving lobe of the polar vortex will dive into southeastern Canada and brush the northeastern U.S. from Friday to Saturday,” AccuWeather Chief On-Air Meteorologist Bernie Rayno said.
Temperatures will take the plunge in the wake of the Arctic cold front.
As the Arctic air sweeps southeastward across the region on Friday, temperatures may fall all day in some locations. Temperatures by mid- to late afternoon could be 10-20 degrees or more lower than the start of the day, especially across New England and the interior mid-Atlantic states.
Winds will average 15-25 mph with gusts approaching 40 mph over the central Appalachians and the mid-Atlantic on Friday. Stronger winds, with gusts between 40 and 60 mph, are likely in New England into Friday night.
The frigid air will rapidly take hold as soon as the sun goes down Friday evening and send temperatures plummeting even further. Gusty winds associated with the Arctic air will result in substantially lower AccuWeather RealFeel® Temperatures.
RealFeel temperatures are projected to range between 30 and 50 below zero where most people live from northern New York state through New England Friday night. In locations at the top of the mountains, such as ski resorts, RealFeel temperatures could dip to near 60 below zero. At the top of Mount Washington in New Hampshire, the weather observatory may experience RealFeel readings anywhere from 80 to 90 below zero.
“Boston is in the running to set a top-five low-temperature mark Saturday morning when the core of the Arctic air will settle over New England,” AccuWeather Senior Weather Editor and Meteorologist Jesse Ferrell said. “Should the temperature bottom out near 10 below zero as data suggests, it will be the fourth coldest morning on record since 1936.” The lowest temperature ever recorded at Boston Logan International Airport was 14 below zero on Feb. 15, 1943.
This looming blast of Arctic air will be the coldest air of the season so far for northern New York and New England and could rival low-temperature marks set during the Christmastime outbreak in the mid-Atlantic.
“It appears that the coldest thrust of air with this outbreak will be aimed at New England with the mid-Atlantic region only in for a glancing blow,” Rayno said.
Although temperatures won’t be as low as in locations farther north, the teeth-chattering cold will still make its presence felt in the major cities along the Interstate 95 corridor. Temperatures in New York City will bottom out in the single digits Saturday morning, while Philadelphia and Washington, D.C., will plummet well into the teens. In portions of the central Appalachians, subzero temperature readings are in the forecast for early Saturday.
Another impact from the brief Arctic outbreak that AccuWeather meteorologists will be closely watching for will be the formation of a narrow but intense band of snow known as a snow squall. This phenomenon, similar to how a thunderstorm moves alongside an advancing cool front, has the potential to suddenly send visibility levels to near zero, drop a quick coating of snow and create a sudden freeze-up.
In the past, similar snow squall activity has contributed to serious injuries and even fatalities due to multiple-vehicle pileups on area highways.
“At this time, it appears the snow squalls may be intermittent and likely to focus from northern Pennsylvania northeastward through upstate New York and northern New England during a less busy time during Thursday night,” AccuWeather Senior Storm Warning Meteorologist Brian Wimer said.
However, forecasters say there is a chance of a snow squall farther to the south and east, possibly reaching parts of the mid-Atlantic and New England coasts on Friday. “Dry air in place will try to combat the extent of the snow squall band and may reduce it to harmless flurries or perhaps snow that does not reach the ground,” Wimer said.
Shifting bands of lake-effect snow will set up off lakes Huron, Erie and Ontario by Friday and may persist into Saturday. However, since prevailing winds with the outbreak will be from the north and northwest, Buffalo, New York, is unlikely to receive much snow this time. The city has endured two separate blockbuster lake-effect snow events since November, including a deadly blizzard that wreaked havoc in the region around Christmas.
Despite the serious nature of the incoming outbreak of Arctic air, it won’t have staying power.
AccuWeather forecasters say temperatures will trend upward by the end of the weekend. The polar vortex lobe will pivot northward this weekend, and that will help to initiate an expansion of milder Pacific air already in place in the West.
Temperatures on Sunday will be 20-40 degrees higher in some areas compared to Saturday morning’s frigid levels, according to AccuWeather Senior Meteorologist Tom Kines.
Boston will climb into the mid-40s by late Sunday, which is slightly above average for early February. In Philadelphia, after a Saturday morning low in the teens, temperatures will approach 48 on Sunday. The normal high in Philadelphia this time of year is in the low 40s.
Produced in association with AccuWeather.
