The forecast is almost a repeat of last week for the region, with continued cold, snow in the mountains on Tuesday and maybe some light snow east of the mountains, and coastal system potential towards the weekend.
Temperatures won’t be as brutally cold this week as it was last week, but we can expect to see temperatures about five degrees below normal through most of the week. A weakening low pressure system will move into the region from the Midwest Tuesday into early Wednesday, which is expected to bring snowfall to the windward side of the Appalachians. Along the coast, we might see some snow flurries Tuesday night into Wednesday morning, but accumulating snow is not expected (though some accumulation in the northern parts of the region is possible).
Late Christmas Eve and through Christmas Day (Fri-Sat), the region could be subject to a large snow storm. At this point in time, I am about 50% confident on a coastal storm this weekend. The snow is expected to start off ahead of the system as it glides in from the Midwest and tracks off the coast. After reaching the Atlantic, this system will rapidly intensify, causing snow to wrap around the storm center and enter the region from the northeast. The confidence in this system is a bit higher because of the good model agreement we have been seeing over the past day or two as the GFS model consistently forecasts a coastal storm. Despite this, we could still run into the same problem we saw with this weekend’s system that ended up out to sea. A more progressive and less amplified pattern would allow the storm to move more quickly to the east, which would prevent the storm from bombing out quickly enough to have a major impact on the coastal areas as it moves further into the Atlantic. There could also be some mixing issues in the southern parts of the region initially, but the big snowfall should not come until after the system has moved off the coast. I will have an update on this system Wed/Thu.
Needless to say, this storm could have some major impacts on Christmas plans from Virginia up through the Northeast along the I-95 corridor. Be extra careful traveling this holiday weekend!