12z DEC 11 ECMWF GOES WOOF .. for DEC 21

[DTWXRISK]

The 12z  (midday run) of the afternoon European models come out and does come up with a interesting solution for day 10 which of the December 21.  There are essentially three different systems coming at us from the southern jet stream over the next two weeks.

 

The first system  is December 17  and the overall pattern and data suggest this Low is  going to track up the Ohio Valley...  Then across Northern New England into southeastern Canada.  This should be a rain event for everybody up and down the East Coast....  and probably even for the mountains.

 

The second event  is December 21 which does look significantly colder  then  DEC 17.  from my  overnight analysis it appeared that this system  will track along the   East coast  as a rain  I-.95. snow for the mountains and mixed over  inland/ Piedmont areas 

 

The third system is the one for December  24.  I remain particularly bullish about the system given how far out in time it is for a number  of different reasons. 
 

All that being said the midday European model has come out with a new wrinkle with regard to the 12/21  East coast Low.  The model ends up keep the cold HIGH in place over the eastern Great Lakes and Western Quebec Canada  on 12/20 and 12/21  and at the same time the  Low in the southern jet stream  comes  out of   TX  ARK LA and   stays  SOUTH reaching the NC coast on 12/21.

This sets the stage for what the  EURO model is  depicting as a significant East Coast snowstorm from the VA/ NC  border all way up into a good portion of New England.  The model.. NOT ME ... THE  MODEL ..  shows significant snowfall accumulations or  implies it for much of the I-95 cities. 

 

We can see this here on the first image.  The  WHITE line represents is  the  0c  850mb   isotherm 

The second image is a enlarged view of the Middle Atlantic region with more detail...   Th

 

The third image is the upper air    500mb of the European model on December  20 showing how this model comes to a solution which produces an East Coast snowstorm.  In this case with the critical feature is the system that goes through the Ohio Valley  12/17.   By  12/20  that Low goes BOOOOM!  Over southeastern Canada and becomes an enormous winter storm for nova Scotia and Newfoundland.  This feature is refer to in the weather business as a  50 / 50 LOW and is critical  with regard to looking for the overall pattern which might support and east coast snowstorm.

 

 

In this case what that Low over southeastern Canada is doing  - the  50/50 Low - is that it  blocks or traps   the  cold HIGH over  the eastern Great Lakes and  western  Quebec  from leaving and moving out into the North Atlantic Ocean.  As a result the cold air stays in place as far south as the ViA/ NC border  -- again according to what this model is showing. 

I am somewhat skeptical about this particular solution but I do not rule it out.  My view was that the something like this was going to happen but a few days later.  I was thinking that this  Low on 12/21 was going to move up into southeastern Canada and become the big  50/50 Low  for ther  12/24 threat.  Therefore I am not convinced that the big snowstorm threat is going to occur with this system on  12/21 as opposed to the one on12/24.  If the model continues to show consistency with the system I may change my mind.

 

BOTTOM LINE ...  if some winter weather lovers  and weenies  could look pass their own internal agony of a mild December... they would see that the fact that we have   already seen 4 significant coastal storms  -3 of which which have been Noreasters-  is indicative of a very stormy pattern and a very active winter.    What we need now with the cold air pattern to return and as long as the southern stream means active....  which it will because of the weak El Nino ...the  East coast winter storm threat is going to remain quite high  for most of January February and march. 

[DTWXRISK]

[negative-nao]

What does tonights Euro Show ?

[Superstorm93]

ECMWF still hinting at something interesting for this time period. 

 

[DTWXRISK]

 12z SATURDAY EURO MODEL DEVELOPS DEC 21 LOW INTO MAJOR EAST COAST WINTER STORM... FROM NC TO MAINE  

The cold air supply is limited... The over all Upper air pattern not great. This is a marginal situation for the interior and rain that ends as snow for the COAST. For western NC Mtns WVA western half of VA western half of MD .. most of PA this could be a SIGNIFICANT SNOW.. COULD BE..


from PHL to BOS again very mariginal on the coast...12z EURO shows wet snow or mix SIGNIFICANT SNOW Inland

did you see the VIDEO???? As I said the KEY is the DEC 17 Low ( all rain for the all fo the east coast) . It is the rapid development of the DEC 17 Low into a BIG Low over SE Canada THAT sets up the DEC 21 Low winter storm threat. 

** IF the big low of SE cnada does not develop or if it moves away .. DEC 21 coastal Low ai all rain for everyone.

 

 

 

 

[DTWXRISK]