Morning Update of Wednesday, December 7th through Thursday, December 8th

Good Afternoon Everyone

I hope everyone is enjoying their day thus far.  Another interesting weather event will be unfolding across New England and Eastern NY come later this evening through tomorrow morning.  This will be a rain to snow event, mainly across Eastern NY, parts of interior Southern New England, and parts of Northern New England.

Surface Analysis:


Currently, there is a stationary front extending from the Canadian Maritimes down to the Gulf Coast.  There are a couple lows or disturbances along the front.  A low over the Carolinas will move to the Northeast.  A secondary low will develop off the Delmarva Peninsula Wednesday Afternoon-Evening and move off the New England Coast Thursday morning.  An area of high pressure is present over the Norther portion of the Province of Quebec.  This will supply some of the cold air into the region.

Storm Characteristics:

The Low will track near or along the stationary frontal boundary

Vorticity Maximum will be present over Southern New England.  Heavy Precipitation (Rain) will occur in this area.

Cyclonic Positive Vorticity and advection will occur ahead and during the storm.  This leads to good dynamical lifting across the region.

The cold air start to move in and push south through adiabatic cooling.  This occurs when you have heavy precipitation and the cold air transitions down to the surface from the upper levels of the atmosphere.


A). Timing:  Periods of rain throughout the day across Eastern NY and Southern New England.  It will be heavy at times.  Rain will gradually move to the north across Northern New England throughout the afternoon and evening.   The Rain will transition over to snow slowly from North to South starting in the afternoon and continuing into the overnight.

The storm will be fast in nature and develop late this afternoon and diminish in the morning for Eastern NY and Southern New England.  The Storm will end in the afternoon for Northern New England.

Winds:
Wednesday: North sustained winds at 5-10 mph across Eastern NY and Northern New England.  Southwest sustained winds of 10-20 mph with gusts up to 50 mph along the coast of Southern New England.

Thursday Morning : West-Northwest sustained winds of 5-15 mph with gusts up to 30 mph across higher elevations across Northern New England. West-northwest sustained winds of 10-20 mph with gusts up to 50 mph across Southern New England and Eastern NY.


Impacts:
-Heavy snowfall from late evening through the early morning hours
-Threat of ice on roadways from the transition of rain to snow.
-Power outrages will occur in areas of heavy wet snow and high winds.

NWS Analysis
GFS Model
NAM Model
HRRR Model
NAM Model