CLICK HERE FOR WHITE CHRISTMAS SNOW EVENT FOR NORTHERN MIDDLE ATLANTIC

The Post Christmas storm has been shown on the models as a storm that will move well to our west and be rain for the Middle Atlantic into the Northeast.  I posted blog a few days ago arguing for the eastward shift starting with the blocking setting up that would prevent such a solution.  Well the GFS has come around in a very big way and shows a big time snow storm for Philly on northward!

One of the reasons mentioned in the blog was the blocking that was very favorable for an East Coast Snow Storm.  The blocking has a tendency to be weakened too quickly on the models.  Another thing mentioned was the phase 2 MJO showing the trough in the Eastern US.  The models have backed off the MJO intensity but the latest IR imagery clearly shows the tropical forcing setting up towards a phase 2 with convection increasing south of Sri Lanka and the rest of the Indian Ocean.  

The EURO keeps the inland solution but look at the lack of blocking:

The GFS shows the block:

Canadian model lso shows the block:

Another bias of the European model might also be showing up and it is related to another factor that argues for the eastward shift.  The active pacific will keep things moving and prevent a very deep trough that destroys the block.  The Euro shows a cut off system in the PAC right off the West Coast that prevents the "kicker s/w" from being deeper and kicking the system further east.  It is the only model that does this and has a tendency to do this.  

The Euro ensembles show an eastward adjustment:

Ensemble support from the GFS is also showing up...notice the inland and warm solution is disappearing from the members below: