Those waking up to temperatures hovering around 60°F (16°C) this morning might be hard pressed to believe that the Institute is in for a bout of wintry weather tomorrow afternoon. It’s true, however: Temperatures are as many as 20°F (11 K) colder behind a frontal boundary that will pass over New England today. This dramatic drop in temperatures will set the stage for a Nor’easter to bring gusty winds and wintry precipitation to the Eastern Seaboard tomorrow.
The storm in question has actually yet to form. Later today, a weak low pressure system over the Gulf of Mexico will begin to be enhanced by a large upper-level trough over the central United States. This low pressure system will deepen, becoming stronger as it moves up the coast during the day tomorrow. In the Boston area, winds will begin to pick up and precipitation will begin as early as 8 a.m.
With daytime temperatures hovering around the mid 30s °F (2°C), the location of the rain-snow dividing line will be highly dependent on the exact track of the storm, with higher snowfall amounts likely further inland. Any snow that does fall during the day will likely have a hard time accumulating on what will be a relatively warm ground surface. However, precipitation will continue overnight, and snow accumulations in the ballpark of 2-4 inches may not be out of the question before the storm moves off to the northwest on Thursday.