A weak low will push out of Mexico into the Gulf of Mexico late Wednesday night as overrunning precipitation develops across portions of the Southeast. Several models suggest that a strip of precipitation will then push over WNC where a near frozen column will be set up on Thursday and into Friday. Other models do not develop this precipitation as far north, and therefore WNC remains dry. Below I will dissect the details of various models, and give you and idea of what I think will occur on Thursday and into Friday around WNC.

Short Range Models More Bullish On Snowfall

The Nam continues to resolve a weak low pressure moving into the Gulf and a precipitation shield blossoming in Tennessee/Georgia and moving into WNC. A massive high pressure will be in place to the north and that will provide a substantial source of cold at most levels. Below you can see the progression on the moisture on the NAM.

As you can see, that low interacts with the northern stream and even some frontogenises occurs where there is some backside snow. Other models are trending towards this solution, but at the moment they are nowhere near as strong with the northern periphery of precipitation. But, we have to give a bit of credit to the NAM solution, because the NAM has been a good model in these fast flows where lots of energy is flying around. So what are other models showing?

Long Range Model Discussion

The most recent GFS actually trended towards the NAM with a much larger expansion of the northern edge of precipitation. We have to watch these trends very closely because they are notoriously under modeled and can lead to surprises around the area. Watch below and you can see how the GFS brings the low out of Mexico and as it interacts with the NorthernJet Stream the precipitation really expands over Tennessee. That will be key for all of WNC to see accumulating snowfall.

Now let’s contrast that with the European model. The Euro has a similar look as the GFS showing the shot at accumulating snowfall. The problem is that these models are not showing a large amount of precipitation. They are showing snow, but not heavy snow or heavy enough to accumulate on Thursday. The NAM is showing a much more juicy system precipitation-wise. Below you can see the Euro.

What you are seeing above is a swath of precipitation pushing into a frozen column around 3pm on Thursday afternoon. This seems to be arising as more and more likely scenario. Long range models are not showing a large amount of precipitation, but I think that that trend is beginning to happen.. and that we will begin to see models produce high snowfall totals over the next 36 hours for WNC. These overrunning precipitation events can be a surprise and can drop 6”+ of snow easily. I am watching this one extremely closely, and I believe this to be our best chance at accumulating snowfall all year.

Let’s take a look at another long range model. One thing that is neat with this model is the backside frontogenises that occurs. You can see that precipitation develop over E TN as the low pressure begins to really strengthen as it transfers to the Atlantic.

Main Takeaway

There is just too much uncertainty right now for me to talk about totals in your backyard, but I do believe the accumulating snowfall of 2”+ could be possible for many around WNC. These overrunning precipitation events are soo difficult to forecast, but I will do my best to keep you prepared if accumulating snowfall moves your way. Look for daily updates now, and regular live videos up until this event. AshevilleWX will be in full force covering the possibility for accumulating snowfall across WNC.