*MAJOR COASTAL STORM DEVELOPING OF THE CAROLINA'S TODAY*
High pressure in control over the area today will make for fair weather conditions with increasing cloudiness and mild temperatures in the low 40's across most of the region ahead of the approaching large ocean storm that will bring fringe effects to a large portion of the area especially near the eastern shores.
Click on images for a larger view
A rich, large and powerful ocean storm is exploding off the coast of the Carolina's today. The placement of the current storm and the environment in which it is in will allow for explosive cyclogenesis this eve and a deepening surface low passing east of the Outer Banks, feeding off the mild sea surface temperature's of the Gulf Stream, traveling northeast until it eventually will pass about 100 miles SE of the 40/70 "Benchmark" at some point tomorrow morning. A pass this far south and east would typically mean a rather minor to non- event for our region, though due to the very large size and intensity of this developing storm, it will brush the region with its western flank bringing accumulating snow, especially to the east & southeast if SNE, gusty winds, large ocean swells and potential for moderate coastal flooding.
The main reason eastern area's see the brunt is the simple fact that it is the area closest to the center of this major ocean ocean storm. In addition to that, the anti-cyclonic flow and an east/northeast wind around the storm puts parts of eastern Massachusetts at high risk for some ocean enhancement and that will be the reason for the likely the highest snow totals. This includes parts of Plymouth and Bristol counties, perhaps western Barnstable County.. The intensity of the winds off the ocean in that ENE direction and the abnormally mild ocean waters means sufficient enough low level moisture (typically tough for many models to pick up on) and a push quite a ways inland of the ocean enhanced snow. Further west across the region will be a very dry, fluffy snow accumulation of a few inches for most as of now as interaction with another low pressure system off to the west of the region and a energetic upper level vortex center swings in from the west . The problem lies in just how much moisture can be squeezed out for central and western SNE under a colder and drier airmass. We will have to watch radar trends today and overnight for this to become more clear.
For now a WINTER STORM WATCH has been issued for most of eastern SNE as well as coastal hazards . The Winter Storm Watch is in effect from Monday morning right through Tuesday morning. A watch means that conditions are favorable for accumulating snow of 6" or more. As soon as the NWS assumes this is likely, it will go to warning at some point. I do have a good feeling that Winter Weather advisories will also be posted at some point today for locations further inland . This is just one aspect of the forecast. Winds and large ocean swells with hit the eastern ocean shores through the day on Monday. Model images below show these additional threats with this incoming system. The Combination of snow falling heavy at times to the east and potential sustained winds near tropical storm force with gusts near 50-65mph likely at the shores brings the likelihood of near Blizzard conditions to parts of the region which will be outlined on the snow map that follows in this post. Gusty winds will extend further inland and create some blowing snow and low visibilities at times. Large waves and swells will bring some coastal flooding at high tide. This is especially the case from Cape Ann to Winthrop into the South Shore of Massachusetts and the Outer Cape and Nantucket .
Below I have put together this simulated Winterized radar loop to give a general idea of what is to unfold on Monday
Snow should arrive from the south during the pre-dawn hours of Monday and overspread most of the affected area by 9am. The brunt of the storm appears to be during the late morning and afternoon hours, and again, focused across eastern sections. While the main storm gets kicked well away from the region Monday evening, snow, scattered at times and of varying intensity will continue for the region right into Tuesday and possibly right into Wednesday as well as a potent upper level vortex and weak low pressure systems swings in from the Great Lakes. There is the likelihood of some inverted trough induced snow as well, just very hard to pinpoint location and time at the moment. Addition accumulations are quite likely at times. Very cold air takes over the region, aided by a fresh snowpack for many into next weekend. It looks quite brutal too ! Deep Winter has arrived to Southern New England. !
EXPECTED SNOWFALL THROUGH MONDAY