Dense fog is currently shrouding the region as humid air flowing over the chilly Atlantic brings the air to saturation. Visibilities are less than 1/2 mile in most places, with some spots down near zero. The fog will linger into at least the first half of Sunday morning and that will be the big news item. Some airport delays are likely due to the fog. Winds from the south will carry milder air later ahead of a cold front approaching from the Ohio Valley. This will tend to dissipate the fog by afternoon in most places.
The cold front, likely accompanied by a few showers, will cross the region Monday morning. Despite the passage of the front, temps will remain very mild as winds from the northwest carry the ocean-chilled air out to sea for a brief time, before the colder air in the wake of the front settles over the area late in the day and Monday night.
The aforementioned cold front will slide into the southern Mid Atlantic States and stall as it encounters a persistent burly upper ridge of high pressure centered near the Bahamas. Several weak jet stream disturbances will move over this front and cause small low pressure systems to travel from SW to NE along it … and much like a rope that is held at both ends and shaken, each one of these lows will cause the frontal zone to bulge north and for precipitation to briefly intensify.
The bottom line is that the Monday through Tuesday night and perhaps early Wednesday will be a cloudy time with intermittent rain. Much of the rain will be light, though with the passing of these little waves of low pressure close to the area, the precipitation intensity will increase. The times that the rain will be a little heavier should be Monday night and again later Tuesday night. In addition, colder air filtering south in the lower parts of the atmosphere will allow conditions to be cold enough to perhaps yield a little snow in northern parts of the viewing area later Tuesday night into Wed. morning.