A very dynamic storm system is on the way for the Eastern US going into this weekend. Widespread areas of heavy snow, freezing rain, sleet, and rainfall are all on the table stretching from the deep south all the way into New England. A classic Miller-B type of Nor’easter.
Storms that come in from the west (up the Ohio Valley) are usually referred to as “Miller Type-B” storms. These storms produce precipitation in the Midwest/Ohio Valley and have a defined surface low that is moving toward the Appalachian Mountains from the west. As these storms approach the mountains, they lose their coherent/compact surface low center and the low re-develops along the East Coast. When this re-development (a.k.a. “center-jump”) happens, the storm can still produce snow over all of the state.
With a storm diving straight from Canada across the Northern Plains will run directly into the sub-tropical jet-stream. Tapping into moisture from the Gulf of Mexico to really give some power to this low. I have a big concern for those in the Western Carolina’s and Northern Georgia regarding the ice threat. With cold air damming present along the Appalachians and the arctic high to the north, this is not a good situation for residents in the Southeast US.
With the energy associated with this system now over land on the West Coast, we are getting a fairly firm track on where this system is going to go. Unfortunately those on Delmarva hoping for another big snowstorm, this is not the one. With a track of the low pressure right over the Peninsula, a lot of warm air will surge in. Although areas may start off as a snow/sleet mix will change over to all rain once the low pressure center gets closer. Our friends on the Maryland Western Shore will have a little bit longer duration of snow and sleet thanks to Cold Air Damming before they will change over to all rain as well.
Those who live along the Appalachian mountains in Western North Carolina, Virginia, West Virginia, and Central PA are in for a doozy of a snowstorm Sunday and Monday. Widespread areas of 6 plus are definitely likely. Areas like Washington DC through Frederick Maryland could sneak in some light accumulations at the start being turning into a sloppy mess once temperatures start rising above freezing when the low approaches.