Here is today's video forecast.
This is a draft map shows predicted snow amounts and starting times. Note how a preliminary patch of snow advances well northward through Pennsylvania before the main precipitation reaches central New Jersey. Eventually, coastal areas will have the heaviest snow. Early tomorrow, gale-force winds and falling, swirling and drifting snow could cause blizzard conditions in extreme eastern Massachusetts (especially Cape Cod).
After tomorrow, a warming trend will spread eastward from the Plains. Instead of snow, thunderstorms and the possibility of severe weather may become the primary focus of attention. The blue line made of the S character shows where the National Weather Service Storm Prediction Center says the greatest risk of severe thunderstorms will be located on Thursday and Thursday night.
Tropical Storm Colin is caught in the southern stream while the northern stream is helping to send unseasonably cool air out of central Canada.
Then, as the cold front arrives, there may be violent thunderstorms. This map shows the early morning SPC assessment of the severe weather risk on Sunday:
Farther east on Sunday, rain is likely to be more extensive, and there is a severe thunderstorm threat from the Middle Atlantic region on south.
With the second front, shower activity may be spotty at first as the system comes through Chicago on Saturday but could be wetter and more stormy than the first front by time it reaches the I-95 corridor Sunday.
A pocket of dry air covers most of the area from the Great Lakes to the back edge of the East Coast clouds. This suggests sunshine will be the rule across the Northeast until the next frontal system approaches later in the week.
Here is the severe weather outlook for today from the NWS Storm Prediction Center. Note at the bottom the population in each alert area is listed. Keep in mind that in any given severe weather situation, the number of individuals directly affected is far less than the number of people potentially threatened.