Stormier Pattern Expected...White Christmas?

We are through the first third of December and so far most of the United States has escaped the cold and snow.  A pattern change is on the way and at least one plow-able snow event is likely before Christmas.  The Pats-49ers game on Sunday may be played in snowy conditions. Until the weekend the weather will be mainly dry with seasonable temperatures.  Overall temperatures will be slightly above average.
combined snowfall from storm 1 and 2 through Dec 20
Dry and calm weather for this period.  Today and tomorrow feature high temperatures in the upper 30's/low 40's for most of Southern New England.  Friday will be near 50 but this is short lived as temperatures drop to 40 by the beginning of the weekend.  Overnight lows will hover around freezing with the exception of tonight which will drop into the lower 20's.

Storm Number 1/Sunday-Monday
144 hour GFS accumulated snowfall forecast valid Monday 7 PM
This is the 00z GFS run for accumulated snowfall off Dr. Ryan Maue's Weatherbell site.  A piece of energy will break off a cut off trough in the west and makes its way across the country.  This system is not a Nor'Easter but will likely deepen once it begins to feel the effects of the Gulf Stream.  Here is the system off the NCEP charts at the 500 mb level and on the surface
While there isn't much to the system in terms of support, there is more than enough for a  plow able snow event
Notice the dip over the Great Lakes.  Here is what the model thinks the surface precipitation will look like
540 thickness cuts across MA/CT/RI border
Temperatures Sunday will support snow
EURO Temps Sunday 7 PM from Dr. Maue and Weatherbell
The weather will be completely different at Gillette Sunday when compared to Monday night.  It might effect the over/under if one is interested in that type of activity.  The EURO has the bulk of the action during the day Monday; the GFS has the heaviest snow during the day Sunday.  Here is the EURO for Monday 1 PM-7 PM precipitation totals
From Weatherbell
I suspect this system dives just south of the New England coast and everyone ends up with snow.  I expect somewhere to get close to 10 inches as these storms can explode offshore and drop a lot of snow in a short period of time.  There won't be much time to recover before

Snowstorm Number 2 Tuesday-Thursday
The timing is unsettled on storm 2 as well.  Storm 2 looks bigger and stronger than storm 1 by far so it is bound to get more attention from meteorologists.  However recent Decembers have featured snowstorm after snowstorm (2011-12 not withstanding).  There was a series of storms in December 2008 in which it snowed for 45/48 hours in the Blackstone Valley that in total dropped over 20 inches of snow. It was right around the 20th as well.  
EURO for 1 week precipitation
Temperatures are much more interesting with the second system as a classic rain/snow line will develop.  The EURO wants to back that line to 495
EURO temperatures.  West of 495/95 will be snow according to the EURO
The GFS has a very strong low pressure system offshore
Strong low pressure with intense precip
GFS is similar with rain along the coast but snow inland
Valid Wednesday 1 PM
What to take away from this- the pattern is changing.  It is not last year as there has been measurable snowfall three times since November 7.  The cold source regions are set to invade the United States for the end of December and January.


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