Carvers Gap

I am going to ride with @PowellVolz on this. I think something is out of whack right now. It is definitely not out of the ordinary for modeling to flip. Happens more than we like. That said, this flip flop stuff from one extreme to the other is odd within short time increments. Might see one flip, and that is it...but not the multiple extremes which we have seen for several days. Maybe it is just extreme cold which is in play. Maybe it is just shoulder season stuff since we are leaving our normal, winter long wave pattern. Maybe there is a computer or data problem. Something is off.

The 12z EPS actually looks very much like the CMC operational.

Regarding mid-late week overrunning event: The 12z EPS pushes the front through E TN at 174 which is later than 0z which was at 114. Everything is similar to 0z until the front hits west TN and then it CRAWLS across the state for nearly 60 hours. So, that creates an extended time opportunity for overrunning. The operational doesn't press the front through E TN until 222! It stalls the front in Missouri. So, there is some support to slow the front, but the actual operational is out of step with pretty much every model at this point....but I don't discount it. The EPS still has the overrunning window while the operational halts the cold in the Plains.

The 12z EPS provides some support for the operational. However, it is not to the extreme extent that it flips the pattern. Still has the overrunning event later next week. Something to keep an eye on for sure...big changes from the Euro should not be taken lightly.

12z Euro is much different than the 12z suite and much different than its other runs. It may be correct and it may not be. I think it is a combination of an error(getting hung up in the West for the umpteenth time this winter only to have it not verify nearly as strong) and a legit MJO trend not to go into phase 8 but the COD. It will be nearly 40-50 degrees warmer in some forum locations for later next week. At this point, I am not buying that extreme of a shift, but there is some trend to keep the cold west of the Apps - that I buy...just not West of the Apps as in Oregon.

This is my opinion, I think the Euro is playing games again in the West. It has a tendency to dig too much out there. This solution was different from Wednesday onward - way different. Just going to have to wait on its ensemble to see if this is a big shift or an outlier. Tendency would be to toss it as of now...but will wait to see the EPS.

Just posted the MSLP comparison anomaly above...

Take a look at this at 174. The big high has just vanished. So, this run is either going to score a massive coup or be tossed as an outlier. I know better than to disagree with the Euro when it makes big changes. However, that is just a massive massive break in continuity. We will see if other models follow suit during the next few runs. New is on the left.

MASSIVLEY different run on the 12z Euro...doesn't fit with its other runs nor the rest of the 12z suite. Completely loses the high over the nation's mid-section later next week...poof. We will see if he ensemble supports that.....

At 144(132 this run...144 0z run), the Euro has again lost a hp over the Plains which is allowing for a more robust southerly flow.

The 12z Euro seems to be beginning the overrunning event on Wednesday. It has a light mix along the KY/TN border where it had none at 0z. That is quite a different look.

Switching back to this thread for the late week look from the Euro....

It is craziness. Was just looking at it myself.

Euro is slightly NW like the rest of the 12z suite. Its western edge of snow accumulation has definitely trended west over the forum area. Looks like modeling is defiintiely relying on the backside of the precip to be enhanced as the system along the coast pulls northward.

Holston has to be thinking right now...might be time to schedule a trip to Kingsport and the EB.

The 12z GFS not any better over middle TN. Looks like the 12z suite really wants to stall the boundary right at the Plateau or Apps - take your pick. Looks like modeling is wanting to come out of phase 7 on the MJO into the COD with phase 8 as a background state. Certainly looks like what we are seeing on modeling right now.

That is crazy, man. I am just looking at who doesn't have ice so I can show up unannounced like Cousin Eddie.

It gets worse...LOL. Wurbus just turned out the lights on most of the forum.

And that is before the big stuff hits....

.7" ice accumulations in portions of eastern Kentucky through 153.

Edit: .3-.4" ice accums through 153 for portions of west and middle TN.

The CMC only takes 150 hours to push the cold boundary across the entire state. That is a wide open window for all kinds of winter weather.

Will depend on precip amounts. The orientation of that axis and slow movement of the front could be a problem. But definitely don't want to lose power and then have record cold. The CMC does not push as much cold eastward FWIW. Stalls the boundary which is why it is bad in terms of zr.

12z CMC is very icy for the eastern valley areas.

The CMC has 4-5 waves of frozen precip which slowly press the boundary eastward.