Challenging Forecast With Models Still not In Harmony!

The moral of the story as we begin the 7th day of december is the guidance that we have to use to try and forecast the upcoming time period of the 11-14th. The guidance that we have to use is still not in harmony and its really all over the place.

After looking at tonight’s guidance it appears the models are no closer to a believable solution then when we first started tracking this.

We have seen Appalachian runners, we have seen Great Lakes Cutters, we have seen coastals. Normally in situations like this one could normally turn to the models ensemble means but lets be honest..they have been all over the place.

So here are the different scenarios at 120 hrs out from 00z..

UKMET

ECM

GGEM

GFS

From looking at the above you can pretty much figure out that it would appear that the UKMET/GFS are on similar solutions and the GGEM/ECM are on similar solutions. Models make strange bed fellows.

So lets fast forward to 144 hrs and see what we have..

UKMET above!

ECM above!

GGEM above!

GFS above!

Pieces of the puzzle become no clearer. Notice the UKMET? Now if you are familiar with the UKMET..the UK is basically the little brother to the ECM. Majority of the time when the UKMET is radically different from the ECM it serves to throw up a red flag!  And in this case …I am throwing up a red flag as well and to show you why it is now time to turn to the ensemble means.

So lets look at each of the models means minus the UKMET due to having no access to them.

Notice how the means of the ECM is radically different from the op?

Notice how the GGEM mean is slightly more east? But more importantly notice how it is very similar to the ECM means?

Now we get even more interesting as we notice the GFS is slightly east of its operational run and pretty similar to the ECM means & the GGEM means.
However…perhaps the most important thing to realize is that the UKMET in its operational run is already showing this.

So in the means of the models we have harmony. In the operationals we have confusion and model mayhem. Its a little to early yet to know whether the means are correct or the operationals are correct but at this time ..Real Wx Service is leaning on the Ensemble means & have been since 3 PM yesterday afternoon when we issued this map.

This is the track that we feel fairly confident with at this point and time..especially since the means add much credence to this map which was created well before 00z models yesterday.

This means that it is still possible for areas to the NW of the low track to receive potentially heavy snow! Of course..if the operationals end up correct we will be looking at strong WAA and snow changing to rain & then getting brutally cold on the backside of the storm.

The truth of the matter is it is just to early to know when the energy does not come on land until Friday! We will probably continue to see an array of solutions..However..its too early in the stage of the game for anyone to be giving up if even the models do not yet know the certain outcome.

Stay tuned for more updates on this developing winter storm!