Significant winter storm Monday

I discussed some of the details of this system on the main page about 36 hours ago, and after a rather dismal start to the model runs yesterday, things arent looking too bad.

First I would like to discuss what happened yesterday. After a series of model runs indicating good potential for a SNE hit, the GFS decided to phase early and send low pressure north to the Great Lakes. With no / weak high pressure to the north this equates to rain. This continued for a couple of runs, but the 00z came in with less / later phasing and low pressure tracking up along the coast.

Starting Saturday in the Southeast: The first short wave stays flat and well out in front of the system that will become out Monday storm. So this wave shoots off of the SE coast and out to sea. The system behind rides south along the Gulf Coast until a short wave drops down out of the large vortex in Canada and phases with the southern storm. Low pressure then rockets northward.

There are notable descrepencies between the ECMWF, GFS, UKMET, and GGEM with regards to the amplitude and placement of the upper level low over the Great Lakes. This results in issues with phasing and timing regarding secondary development. The main missing ingredient for a major snow storm is strong high pressure to the north. Without this, warm air is free to ride into New England on strong southeast winds. So this presents significant ptype issues that could be the difference between a coating of snow and a foot of snow. At this point, with a trend east in the coastal low, the prospects of several hours of frozen or freezing precipitation looks good. This system will have excellent dynamics with strong omega to provide a period of heavier precipitation Sunday Night into Monday morning. The track of the low pressure could however place us in the dryslot early, so that is another variable to watch.

All in all, many unanswered questions floating around. One thing Im confident on is a very intense storm system affecting the eastern third of the nation in 96 hours.