Cold air building over the Central states will expand toward the East during the balance of the week and will be accompanied by snow in some locations.
Temperatures will be slashed by 20 to 30 degrees compared to the start of this week.
High temperatures mainly in the 40s during the later part of this week will replace highs in the 60s in New York City, Philadelphia and Washington, D.C. AccuWeather RealFeel® temperatures will plunge into the 20s and 30s at times during the daylight hours.
However, the temperature drops will not be as extreme in the East as they were over the Central states.
The air will get cold enough at night to bring the first freeze to portions of the South, including Atlanta, and the Interstate-95 corridor.
Unlike chilly air episodes thus far this season, this particular cold outbreak will have staying power and is likely to last well into next week.
In much of the Appalachians and many areas on the western slopes of the mountains, high temperatures most days will be no better than the 30s.
Bands of snow and flurries will set up downwind of the Great Lakes.
The first areas to experience the lake-effect snow will be across parts of Michigan and northern Wisconsin in the immediate wake of the Upper Midwest snowstorm.
According to AccuWeather Chief Meteorologist Elliot Abrams, “Some areas around the lower Great Lakes that have escaped lake-effect snowfall thus far this season will have their first accumulation later this week.”
Abrams expects enough snow to fall on parts of northeastern Ohio, northwestern Pennsylvania and western New York to make roads slippery.
From Cleveland to Erie, Pennsylvania, and Syracuse and Rochester, New York, lie within this swath of potential rounds of snowfall and slippery travel beginning on Thursday and lasting through the weekend.
A developing storm system along a reinforcing push of cold air will cause some wintry trouble in part of the Northeast Thursday night.
The system will bring a period of snow or rain changing to snow from the Pocono Mountains of northeastern Pennsylvania to the Catskills of New York and part of New England. A few inches of snow are forecast in the Poconos and from interior southwestern New England to southeastern Maine. There can be slushy travel in this I-95 swath, including some slippery spots in the cities of Hartford, Connecticut, Portland, Maine and Boston before the system moves away Friday morning.
Mostly rain is in store from Philadelphia to New York City, but some wet snowflakes can mix in at the tail end Thursday night. Rain is likely to fall on Long Island and Cape Cod.
During Sunday night into Monday night, another wave of cold air will approach with a larger storm tagging along.
While this storm will bring mostly rain to the mid-Atlantic and southeastern New England, it cold air may return fast enough to bring a change to wet snow before ending from parts of the Appalachians to some of the northern and western suburbs of the I-95 cities.
The amount and extent of that snow will depend on the strength of the storm and the speed of the reinforcing surge of cold air. A very weak storm and fast-moving front may translate to only spotty showers of rain and non-accumulating snow for much of the region.
More details on the cold air, lake-effect snow and potential storms will continue to unfold on AccuWeather.com.