Carvers Gap

12z CMC also has the overrunning event for later next week. It is a bit further east and less cold. I think we are looking at the potential for the front stalling at the spine of the Apps and/or the Plateau. Edit: Well some of it must get past the Apps as there is also a decent CAD signature for NC during part of that event.

@AMZ8990, that right over your house?

Edit: It is in agreement with its operational. The different snow algorithms are messing with my mind.

The 12z GEFS mean is stout for much of the Plateau and eastward.

Yep, think it is a problem for those in the foothills on the west slopes. Agree.

The trend at 12z is a big move northwest with the snow axis. The CMC has now placed the northern Plateau in the game. If the CMC is correct, would think Monterey and Crossville would be in the game now. It is crazy how far west this has come since 0z. I just don't think modeling has caught up so I am not sure where this ends up....

Give it a day or so, but may be time for a separate thread for that cold shot and potential overrunning event. If modeling is even halfway correct, that event could be significant for many in the forum area - if not ice, then severe cold. Really tracking two events right now...the system this weekend and the cold/potential overruning event later next week.

Man, going to get ridiculously cold if we get frozen before that cold shot. The scenario is there where we could have wide spread power outages prior to a really severe cold outbreak.

So here is why this is so difficult to predict. Think about how a hurricane when it is approaching the coast at a 90 degree angle, the cone is easy to set for the most part. Now, if the hurricane is running parallel to the coast...much tougher. Any degree of change to a storm running parallel to the coast could result in hundreds of miles of changes in landfall forecasts. Pretty much the same deal with this overrunning event next week. The slightest change in angle of that boundary is moving that frozen boundary all over the place.

The trend with the 12z GFS is to push further south with the cold post 100.

I think what is happening is the SER is going to fight east of the Apps. To me, this looks like cold moving across the entire forum area and banking up against the Apps in reality. As BNA noted(think that is right) having a front draped SW to NE is a recipe for winter weather.

Big 1057 high in WY at 186.

1054 hp rolling in around 168. That is a nasty, nasty setup.

There may be 1" of liquid equivalent falling in the form of ice, sleet and snow in west TN. Also working into middle TN as well...

Middle and western forum folks might want to turn their attention to what is going on just after 100. I am keeping that conversation in the main thread, but that is an impressive mess!

That is a major overrunning event in middle and west TN which is being portrayed on the 12z GFS. Wave three of ice now inbound.

The 12z GFS has a light wintery mix over middle and western forum areas just after hour 100. There are at least two waves of this. Very icy look.

Agree.

Not to change the subject, but the GFS is much more impactful with the second system...will jump over to the other thread for that.

Additionally, we may be seeing the system experience some "sheer" from the Smokies. If it continues to back west, we get a better system and the sheer is reduced. Right now, the spine of the Smokies is just shredding the moisture transport into the region. One more shift, and I "think" that would improve.

The 12z CMC is going to be a good test. It has a very sharp snow axis gradient on its westward side. If it shifts, we should easily be able to see it.

I think we want a more consolidated system and better phase. Not sure if that happens, but that would overcome the downslope IMO. TYS and TRI really need the slp tracking more west of where it is. I don't think the backing will hurt us, but having a strung out system which is in two parts will cause all sorts of problems not the least of which is getting dry slotted.

Northerly component meaning the axis of snow has shifted more to a "due north" look than sliding to the NE. So, NNE vs just NE if that makes any sense.

The storm itself has a more northerly(vs east) component to it than it has had during the previous two runs on most modeling. In my book, a storm which is backing(and on the coast) is a good thing. Obviously we don't want it backing if it was in the Piedmont. Someone had suggested downscoping might be a factor, and that might be what we are seeing in the Central Valley. Not sure. A really consolidated storm like the NAM is what we need. These sort of strung out solutions where the phases is late or partial don't cut it. I think the trend is for a strengthening storm. Again, very little runway left as this begins tomorrow. Pretty big move west.

Both