MDScienceTeacher

There is a ton of agreement 174 hours out that a big storm is going to set up along with a trough over the eastern half of the country. Look at the agreement in the clustering of lows over Colorado. Thats our storm for the 1/14 - 1/15 period: Now look at the 500 MB height anomaly a couple of panels later: The trajectory of the isobars (WSW to ENE orientation) out in front of the upper level low steers that the storm just to our south. The low pressure out in the Atlantic also forces things to our south and reinforces cold air. It's a nice look IMHO.

I have been reading this discussion all morning. Is this the farthest things go back with reasonably reliable data?

It's my number 1 in terms of dynamics - ie thundersnow, rates, accumulation over a short period. Just an insane event.

I have been reading up on Anafront snow events and the key ingredient is the speed and direction of the forward motion of the front along with the wind direction behind the front. With a slower moving front and wind direction behind the front oriented perpendicular to the cold front, there is a local zone which can still produce enough "lift" in the atmosphere to produce precipitation. I would need someone who knows what they are talking about to explain better, but my suspicion is that the blocking to our north and east slows the system down enough to produce the anafront anomaly.

This

This is a completely different set up. In 2011 the upper level vort passed just to our south making it a nearly perfect vort passage. There was crazy dynamics with that storm.. but it was a more of a "standard" set up with a storm passing just to our south. This is anafront snow. And in order for anafront snow to work a lot of things need to come together perfectly. Many times the models will over due these ingredients and show accumulating snow for our region but once it comes we wind up seeing only flurries on the back side of a front.

The difference in the set up btw the GFS and the Euro can be seen clearly here at the five day mark. Look at the low pressure aloft over the North East Canada: This feature looks to steer the upper low diving south out of Canada all the way down in to Northern Alabama. At the same time on the euro, there is ridging out in front of the upper level low which allows the storm to cut. The 12Z/ 18Z GFS basically looked the same wrt to the overall upper air pattern.. definitely not a step towards the euro imho.

I cant believe that just happened

We are good.

Meaning you don't want snow til after Christmas or "It just doesn't snow before Christmas around here"?

To me it looks like a timing issue with the initial wave getting way too far out in front of the northern stream low diving out of Canada. Now those pieces don't go boom until Christmas when everything as already progressed past us. The good news is that the pattern says blocking. And I am pretty sure that blocking means that progression will get slowed and the energy will get pushed further south as the models come into focus. Fingers crosses LOL

TT only goes back 7 days.. but it nailed it in the 7 day window:

As these things come in to resolution, I feel like the models will sort out/ consolidate storms wrt to timing. Thats my guess but who knows how these things work under the hood. In my household everyone looks at the models. We have a family limit - 156 hours. If the storm is inside 156 hr, we are allowed to get psyched up over it. Otherwise, it is fantasy land. I guess tomorrow is the day we can start getting stoked.