As mentioned in my previous post, high pressure will move in for the weekend behind a cold front that moves through Friday morning. The frontal boundary will stall to our south.
For Saturday and most of Sunday, we will have mostly sunny skies but with temperatures below average, in the 30s.
The stalled frontal boundary will become associated with a developing low pressure system in the Midwest and will redevelop as a warm front, moving slowly north as it tries to displace the cold air at the surface.
Warm air will start to overrun the cold air with an initial weak impulse that may bring some light snow late Sunday night or before daybreak Monday. (This looks to be very insignificant.)
As the warm front slowly approaches Tuesday, snow may develop Monday night into Tuesday, but it appears that it will mix with sleet and change to all rain sometime Tuesday. This is the most likely scenario.
But, there’s significant disagreement among the models with this system. While the change to all rain (after some freezing rain) is the most likely scenario, the GFS and FV3-GFS suggest a secondary low develops along the Delmarva coast, possibly allowing more snow. The Canadian model is similar but maintains much more cold air, with more snow. The European model has a much later development into Wednesday, with the secondary low developing north in New England, giving us mostly rain.
The Tuesday through Wednesday timeframe looks interesting. Stay tuned.