Carvers Gap

Check that...looks more like an AK block with some AH high mixed in....

In the LR, looks like the trend is to retain the Aleutian high. Still a long way out there, and modeling looks out of sync with their MJO plots. GEPS took a step to the GEFS at 12z - though certainly not extreme as the GEFS. So, for now looks like we have a window for winter weather with the front that passes through, then a strong warm-up, and then TBD around the 10th.

The 6z CFSv2 started to look likes MJO plot. Something is way off regarding American modeling and their MJO plots at CPC.

Yeah, the 12z GFS doesn't even look realistic in its run, eventually stringing together lots of small vortices and rotating them around that high. May happened, but will have to literally see it on a satellite to believe it. Looks like The Day after Tomorrow when it starts stringing vortices together in a line like it does at the end of its run. LOL. This is 384 which I normally wouldn't show, but the model is doing some weird stuff in the LR. It may verify, but the likely feedback problem on the model is producing this.

The GFS is leaving the Aleutian high in place after a brief relaxation in the pattern, and that is certainly realistic. If that slp kicks off the Cali coast after Jan 3 it likely doesn't allow the AH to rebuild. That vortex backs the flow and reforms the AH.

To me, the past three runs of the GFS seem to struggle with feedback and the western slp after the 3rd. It just sits there which digs the downstream ridge. The CMC does not have this nor does the EPS.

The weaker GFS solution is actually allowing for less suppression in the short run. My guess is the cold front is more CMC-like and less GFS-like. You can already see the second front reloading on the CMC late in the run.

The GFS right now is producing solutions which are far, far different than its own MJO or other global operationals. It is either about to score a coup, or it is struggling. Its cold front on the 3rd is much weaker than the CMC or ICON. Seems like an error, but time will tell. Large difference begin then.

6z GFS plasters portions of middle/west TN. You all need to head tot he Midwest/Ohio to see the comments which were posted from their local NWS disco statement. I often read the MA forum, because a lot of their weather begins IMBY. If I lived in middle/west TN, I would get my hands on that post given what we saw the GFS just do. The CMC has a storm further east. Euro, as expected, is slower and more west than the other two solutions. 12z might be an interesting suite if models keep showing that look. My guess would be middle and west TN for now - but low confidence that modeling has this sorted out. It could simply cut well west of the area. In the LR, the past two runs GEFS has little support for its solutions at 0/6z, even from its own MJO plots. Could be a coup and leading the way or it could be dealing with feedback from a slp which stalls along the west coast as a result of a split trough. The GEFPS and especially the EPS have excellent solutions which would produce winter. For now, I go with the GEPS/EPS combo. What is weird is the GEFS MJO looks fantastic! Wonder if that model might be getting ready to move yet again. Tough pattern for models to work out. LOW CONFIDENCE in timing of the potential next cold shot after the 3rd-5th. Would guess it is around the 10th, but we will see. American modeling looks significantly worse today, though their MJOs looks textbook for cold. Something is going to have to give. The actual 6z GFS looks reasonable though. Holston has given a great rundown this morning. Questions still which need to be answered over the next few days. Is this a pattern relaxation which simply returns to its December form? Is this a new pattern which may still put the trough out West? Or is this a return to the November pattern in a step down fashion during January? Again, it is super important to look at the mslp under those 500 looks. Some of those looks are terrible at 500, but the surface map is below normal. I say that because the 500 look has been fooling me for days, and the MSLP tells a different story. Great write-up, @Holston_River_Rambler

Yeah, the CMC is similar to the GFS regarding the possible event for the 3rd.

0z GFS rolls the AH into Alaska and forms a mega block. Should set the stage for a strong Arctic outbreak around just after that storm comes on board at 264. Just another iteration of the possibilities once the pattern begins to shake-up.

2-4" over portions of E TN as well....perfect tract for snow here. Was reading the thread for the Midwest...one of the forecast NWS discos there talked about a storm working from the GOM northward being a possibility next weekend.

0z GFS commentary(will update this post as it runs): @162 winter storm incoming/underway definitely can see the GFS is working off a different MJO scenario despite a great winter storm track GFS does get there...still think it is dealing with some severe feed back issues with the system that doesn't come on board. Pretty obvious the MJO for the GEFS is a bit different than the CMC's Stay tuned for 6z...should be more model mayhem.

And it should be noted that modeling is going to be all over the place with cold on the move.....again, the 18z GEFS looks fantastic. Just trying to get the pattern right for now.

Nice cold front rolls through 3-5th. Takes a little longer to reload. The 18z GEFS holds to a quicker reload after the first front. Again, take a look at what @Holston_River_Ramblerhas posted above. Nice, stable quad groupings. Then, roll that forward into the 300s and the GFS is juggling 7-8. I think cold is on the table. Models just don't know which piece of energy or amplification to jump on. Likely will be some HUGE swings in actual reality. Model mayhem may be on the way - which I like!!!

18z GEFS through 300 looks really good.

And roll that forward into the 300s and all of that just scatters. Crazy what is in the LR right now. Not sure modeling is equipped for where it goes after that map above. It is a beauty though.

Below are two contrasting months. By no means am I saying this is what happens. However, sometimes to illustrate something, an exaggerated example is often helpful. La Nina winter with incredibly warm temps followed by a very cold January. Yes, this pattern is rare. It was rare then, and it is rare now. 71 degrees to start January. If we hadn't had that 26 degree AN departure to start the month....So, this is why I have learned not to quite on winter while in December. Lots of lesser examples exist. Click column heading to sort ascending, click again to sort descending. Date Temperature HDD CDD Precipitation New Snow Snow Depth Maximum Minimum Average Departure Sum 1758 1061 - - 599 0 1.76 0.3 - Average 56.7 34.2 45.5 6.2 - - - - 0.0 Normal 49.5 29.2 39.3 - 795 0 3.76 1.7 - 1984-12-01 51 31 41.0 -1.1 24 0 0.00 0.0 0 1984-12-02 59 27 43.0 1.1 22 0 0.08 0.0 0 1984-12-03 53 33 43.0 1.3 22 0 T 0.0 0 1984-12-04 38 23 30.5 -11.0 34 0 0.00 0.0 0 1984-12-05 42 35 38.5 -2.8 26 0 0.28 0.0 0 1984-12-06 40 12 26.0 -15.1 39 0 0.13 0.3 0 1984-12-07 30 10 20.0 -20.9 45 0 T T T 1984-12-08 49 16 32.5 -8.2 32 0 0.00 0.0 T 1984-12-09 55 22 38.5 -2.0 26 0 0.00 0.0 0 1984-12-10 45 32 38.5 -1.8 26 0 0.03 0.0 0 1984-12-11 57 37 47.0 6.9 18 0 0.00 0.0 0 1984-12-12 62 31 46.5 6.6 18 0 0.00 0.0 0 1984-12-13 67 45 56.0 16.3 9 0 0.00 0.0 0 1984-12-14 69 36 52.5 12.9 12 0 0.00 0.0 0 1984-12-15 71 38 54.5 15.1 10 0 0.00 0.0 0 1984-12-16 65 39 52.0 12.8 13 0 0.00 0.0 0 1984-12-17 64 44 54.0 14.9 11 0 T 0.0 0 1984-12-18 60 42 51.0 12.1 14 0 0.01 0.0 0 1984-12-19 62 51 56.5 17.8 8 0 0.08 0.0 0 1984-12-20 59 51 55.0 16.4 10 0 0.08 0.0 0 1984-12-21 64 51 57.5 19.1 7 0 0.04 0.0 0 1984-12-22 60 35 47.5 9.2 17 0 0.26 0.0 0 1984-12-23 51 27 39.0 0.9 26 0 0.00 0.0 0 1984-12-24 48 25 36.5 -1.5 28 0 0.23 0.0 0 1984-12-25 50 28 39.0 1.2 26 0 0.22 0.0 0 1984-12-26 59 25 42.0 4.3 23 0 0.00 0.0 0 1984-12-27 59 38 48.5 10.9 16 0 0.00 0.0 0 1984-12-28 69 39 54.0 16.6 11 0 0.00 0.0 0 1984-12-29 69 41 55.0 17.7 10 0 0.00 0.0 0 1984-12-30 64 46 55.0 17.8 10 0 0.08 0.0 0 1984-12-31 67 51 59.0 21.9 6 0 0.24 0.0 0 Click column heading to sort ascending, click again to sort descending. Date Temperature HDD CDD Precipitation New Snow Snow Depth Maximum Minimum Average Departure Sum 1112 598 - - 1153 0 3.21 9.7 - Average 35.9 19.3 27.6 -8.8 - - - - 0.8 Normal 46.5 26.3 36.4 - 886 0 3.65 3.0 - 1985-01-01 71 56 63.5 26.5 1 0 0.33 0.0 0 1985-01-02 57 38 47.5 10.7 17 0 0.71 0.0 0 1985-01-03 44 38 41.0 4.3 24 0 0.34 0.0 0 1985-01-04 42 31 36.5 -0.1 28 0 0.32 T 0 1985-01-05 31 26 28.5 -8.1 36 0 T T T 1985-01-06 46 20 33.0 -3.5 32 0 0.00 0.0 T 1985-01-07 39 29 34.0 -2.4 31 0 T T 0 1985-01-08 38 31 34.5 -1.8 30 0 T 0.0 0 1985-01-09 43 20 31.5 -4.8 33 0 0.00 0.0 0 1985-01-10 38 32 35.0 -1.2 30 0 0.02 T 0 1985-01-11 37 23 30.0 -6.2 35 0 0.06 T 0 1985-01-12 29 17 23.0 -13.1 42 0 0.01 0.1 T 1985-01-13 36 13 24.5 -11.6 40 0 0.00 0.0 0 1985-01-14 41 15 28.0 -8.1 37 0 T T 0 1985-01-15 29 16 22.5 -13.5 42 0 T T 0 1985-01-16 42 11 26.5 -9.5 38 0 0.11 1.1 0 1985-01-17 35 29 32.0 -4.0 33 0 0.21 2.1 2 1985-01-18 36 26 31.0 -5.1 34 0 T T 2 1985-01-19 35 25 30.0 -6.1 35 0 0.10 0.9 T 1985-01-20 25 -16 4.5 -31.6 60 0 0.21 2.1 3 1985-01-21 2 -21 -9.5 -45.7 74 0 0.00 0.0 3 1985-01-22 20 2 11.0 -25.2 54 0 0.02 0.3 3 1985-01-23 24 11 17.5 -18.8 47 0 T T 3 1985-01-24 39 4 21.5 -14.8 43 0 0.00 0.0 2 1985-01-25 37 15 26.0 -10.4 39 0 0.01 0.1 1 1985-01-26 22 10 16.0 -20.5 49 0 T T 1 1985-01-27 27 5 16.0 -20.6 49 0 0.10 1.0 T 1985-01-28 32 24 28.0 -8.7 37 0 0.13 1.8 2 1985-01-29 31 15 23.0 -13.8 42 0 0.00 0.0 3 1985-01-30 40 15 27.5 -9.5 37 0 0.02 0.2 1 1985-01-31 44 38 41.0 3.9 24 0 0.51 0.0 T

If you really want to see how complex the pattern is about to get, go to the NH view of the 18z GFS and look at it at 500. Once the Aleutian high(edit) is dislodged, chaos ensues. Model mayhem is likely on the table at this point. To me, I would suggest the potential for a progressive(but slow) pattern. Versus things getting locked in, we may well see things move...but slowly until things shake out. What is on modeling is a major disruption to the atmospheric circulation. I think we are about to see an amplified, short wavelength pattern. It is almost like the big Aleutian high was a cotter pin - kind of held things in place.

The 18z GFS may be right after Jan 5th, but that is a bizarre run with not a ton of support from other modeling. Looks like feedback problems to me yet again. Let's see if its ensemble supports that. I will say....the BIG problem is that we have 7-8 vortices rotating counter clockwise around those AN heights that was dislodged from the Aleutians. If you go to the northern hemisphere view, you can see them orbiting in what looks like drones just circling a mother ship. Models are not handling that well at all, and understandably so. Below is the Euro at 12z at hour 216. Amazing, but good luck to numerical model sorting this out any time soon!!!! ....To all the models at 0z, may the odds be ever in your favor.

I doubt it. Definitely on the sauce at 12z. LOL. I was getting ready to bust on it until I stumbled across this in my search. This is its look for Dec 29 to Jan 5. Yes, first part of that is going to be warm but the time from from Jan 3-5 could be very cold. But look at the date this was made....

@Holston_River_Rambler...always great photos Not sure I have ever seen something like this before. This is the 12z CFSv2 control. These are -20F departures for western portions of the forum area......for a 30 day time frame. LOL. The mean is 5-10 BN which is just insane in an of itself. This is why I don't share a foxhole with this model...but, man.

Jax, if the SST build in the western Pacific, that would likely allow more convection to occur in the MJO regions 8-1-2, right?

LOL. Check out these 24 hour temperature changes from Jan 2 to 3. First is the CMC and the next is the Euro. The CMC is at 6z on the 3rd and Euro is at 12z on the 3rd. GFS is a mere 25-30 degree temp change.

After the weather we are having right now, if we go BN for part of early January that is gonna hurt! Just sayin.........