Mount Holly's updated AFD on this "threat"-
As we move into Tuesday, the day will start off quiet as high pressure moves out to sea and weakens. This will allow for an area of low pressure to move offshore of the Mid Atlantic region to our south by Tuesday afternoon, then strengthen as it moves northward offshore of Delaware and New Jersey coasts. This will likely bring a period of precipitation across the area, especially along and south and east of the I-95 corridor, and mainly across southern New Jersey, southern Delaware, and southern Maryland. If the precipitation begins early enough, it looks like it will start as rain for many areas. However, as the low wraps up as it moves closer to the area, colder air will wrap around the low and the precipitation will likely mix with or change over to snow. While all of the guidance indicates a transition to snow, only the 12z NAM has a significant accumulation. For now, we`ve sided more with the GFS, ECMWF, WPC and have mostly a half inch or less. Temperatures may be too warm for significant accumulations to occur, even though there could be a period of heavier snow due to strong lift within the dendritic zone across southern New Jersey, southern Delaware, and southern Maryland.
eta- when they refer to "southern MD", they mean the southern most extent of their MD eastern shore counties, i.e. Talbot and Caroline.