Carvers Gap

@John1122, you watch the ICON pretty closely. What is up with that run?

LOL. I came here to ask if I was looking at the map wrong.....it is THAT different!!! Like it isn't even there.

I would add that modeling that is digging into the southwest too much...beware. I also think spacing between the Jan 6 system and the one in front of it are critical. When the spacing is less, there is less ridge between then. The smaller that ridge, the flatter the system.

We haven't just lost the deterministic Euro. We have lost the EPS top to bottom. It has thrown out some really strange runs of late(just every once in a while after being rock steady for more runs than I can count). Temp wise, it has lost a good chunk of the cold as well - entire run. I think what is going on right now is that modeling is struggling with very cold temps coming into NA along with a complex storm pattern. Right now, I don't trust any of them. However, the 12z GEFS and GEPS seem to be pretty steady without any breaks in continuity. For now...for now...I ride with those two and toss the EPS. Operational Euro is probably good through d6 or d7. I would suspect ice to rain for Sunday....but I don't trust any model right now. Ride with the ensembles until things settle down a bit. We generally go through wild swings when cold air is in play. Also, when do models lose storms? Yep, bout right now.

12z CMC was a pretty significant ice storm for much of the state.

12z CMC is a slider across the TN Valley w/ a front end episode of ice....E TN is susceptible to this if it comes in at night or early morning.

That was a significant ice storm followed by heavy snow or maybe the reverse is true....it got pretty convoluted.

Portions of W TN got 1.25" of ice AND 17" of snow.

The Kuchera clown map is gonna look ridiculous.

So this was a southern slider. To recap, the system came in slightly north of where it did on the West Coast at 6z. The system in front held back a bit, and didn't allow heights to pump in front of the Jan 6 system. A big 1040 sat right on top and pushed it south. Plausible. But is it right? In the words of George Washington on SNL, "Nobody knows."

at 147, they system is stalled over central Alabama with snow breaking out into the Carolinas.

144, and heavy snow and ice are breaking out across the eastern sections of the forum.

Just checking to make sure this is indeed the right day of this model run...major winter storm for the TN Valley at 138 and 141.

at 135, this is a pretty significant winter storm for W TN as the slp is crawling.

At 129, system is slowing as it is having trouble cutting into the hp just to its north.

At 123 a winter storm is breaking out across W TN...mostly snow.

at 111, significantly less ridging is in front. 1043 high is out front and over the top. Flow is flatter. This might be different than 6z.

12z GFS is rolling. Flow is flatter. Sorry coming onshore at 60 is slightly further north. 12z ICON was a textbook cutter.

I think you all know your microclimates better than I do. The Euro practically has no icing at all or frozen precip south of the TN/KY border. When I say that, that is with respect to lower elevations. The Plateau and the Smokies would probably be a different forecast. The GFS and CMC still have some ice...GFS particularly. Trends overnight and at 6z are more toward rain.

Good news for the longer term. Really, I am pulling for Chattanooga to get a score. This type of cold could bring chances for that area.

I will probably keep tracking this weekend's system while knowing that rain is the more likely solution than not(for the majority of the event...and front end thump implied). That said, the 6z EPS is colder while the 6z GEFS is warmer(still ice). As MRX noted, much of this uncertainty will get cleared up with time on wx modeling. I think the potential for ice is in the eastern valley and along the TN/KY line.

If it cuts enough, severe is on the table. For now, I think the front end thump seems more likely, but the UK solution can't be ruled out.

Just some morning thoughts.... 1. Unless modeling comes back around today or tomorrow(still 5 days out), I think the weekend system is a sloppy mess or just rain. The problem with the eastern valley is if cold gets trapped. I won't even begin to touch the ice situation potential until much closer to the event. MRX said as much this morning, i.e. very tough forecast. Significant snowfall looks increasingly unlikely. 2. Temperature moderation on modeling, but still very cold. Honestly, thankfully we are seeing some temperature moderation on modeling. If we want snow, the southern extent of the cold has to lessen. And I honestly don't like crazy cold wind chills. 3. We may whiff on this weekend's system, but as Holston noted, there are opportunities after this one. 4. Cold is likely going to come in 4+ waves. These resupplies will likely bring snow with them, or connect with moisture from the GOM. This colder pattern will slowly burn itself out beginning maybe around Jan 20th. 5. There is always a chance this is cold and dry due to the trough axis being a bit too far to the east. That said, I do think we score on northwest flow events at the very least. 6. When the NE TN/SW VA/ SE KY snow mean is juicy, that is usually a good thing for everybody else. The GEPS and GEFS look really good. The EPS is less, but respectable. 7. I think North Carolina will break their snow drought. 8. The colder analog package for January likely runs up the score through Jan 20th. Then the warm analogs may well try to pull back some ground. BN for the month seems likely though. 9. February? I think it goes warm but w/ 2-3 pushes of cold air. I think March goes cold. The interesting thing about big cold snaps is that sometimes we break for spring right after. So, a warm March wouldn't surprise me either. 10. Remember that ensembles are probably better when outside of d6 or d7 - reminder goes for me as well!!!!

The 0z CMC was more of a transfer of energy from the TN Valley to the NC Piedmont. Both the GFS and CMC get energy to the coast….I think that is the likely outcome however that ends up. Slider or cutter or Miller A(now part of the equation). Ice looks probable.

0z CMC is ice and then cuts. ICOn and CMC are now cutters. GFS is now a suppressed slider. Whiplash!