The model consensus is for the primary low to form off the Georgia and South Carolina coast late Monday night, which, quite frankly, is amazingly far south for this late in the season! However, given the strength and depth of the arctic air in place ahead of it, it's perfectly reasonable to expect. Then, as the storm moves northeastward over the comparatively warm waters of the Gulf Stream, and the second feature quickly approaches from the west-northwest, this storm should literally explode Tuesday afternoon and Tuesday night, tracking toward the Gulf of Maine Wednesday. Look at the 0z GFS forecast for 18z Wednesday:
That's about as nasty of a nor'easter as they come, and it will cause all kinds of disruptive problems along the way. The most obvious of those is the potential for snow, potentially crippling snows, from parts of North Carolina and Virginia to New England, depending on the track of the storm. There will also be the problem of power outages from strong winds, coastal flooding, beach erosion and the like. This has all the earmarks of a destructive storm, and my guess is that southeastern and eastern New England will bear the brunt of it when all is said and done.
The one 'good' side note from the storm is that after it blows by and reinforces the arctic air, it will all lift out to the northeast quickly. That means a quick snap back to normal by Friday and Saturday, if not above it, and the promise of a milder pattern to open up April!