Winter Storm Watches HOISTED..

I'm impressed with the National Weather Service from Roanoke- they just went BIG!

Winter Storm Watch western areas 4-8 inches possible (Including Roanoke, Blacksburg)

Winter Storm Watch eastern areas 6-14 inches north of the Staunton River. (Campbell County, Lynchburg north and east)


And, they may go down in flames. :( My confidence is not that high.


It's a battle of the models.

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1.GFS, NAM, and SREFS: The crank up the low a JUST smidge north and east and we get mainly rain as the incredible snow bands sit somewhere closer to Charlottesville.

2,GGEM, Euro and UKMET are more south with the low and keep a heavy band, especially over northern and eastern areas much of Wednesday.

What do these have in common? The First set upload data in something called 3dvar (3d variational data assimilation) and the second in 4dvar (4d variational data assimilation)

4dvar is an upgraded model and has tested to be superior in the big picture, but has lost some individual events so to speak. The NAM and GFS has both showed the big event at times, but the overall trends have been a NEAR miss. The Euro has been consistent and just varied a little the strength.

What is the differences on a functional level?

The biggest differences is how quickly this storm "winds up" and exactly where. The 4DVAR models are convinced it will be more to the south and west and hang that thing back longer to get us under a good snow band for hours. There are a ton of players this system.

What do you think, Keith?

I'm so glad you asked. :)

Confidence is low. The consistency of the Euro I like, despite being a little south of it's ensembles. (Ensembles are the same model run 50 extra times with minor changes to weed out flaws in modeling)
However, at this time I would have liked to see the 3DVAR group move towards the 4DVAR group. They flirt, but don't commit.

Some of the models literally every 5 miles you head North east out of Lynchburg ads an inch to your total.

My current guess-
Blacksburg and Roanoke 3-6
Lynchburg  4-8
Amherst Appomattox- 6-10 maybe more in the higher elevations.

If the banding sets up a tad south, these could be higher, especially Lynchburg region.

Per the norm, will update this later-- not a lock at all. When banding sets up, it gets crazy-- like trying to guess exactly where a thunderstorm will form.