Carvers Gap

Less subtle hint...the 12z GEFS ensemble runs looks good as does the EPS. That energy getting held back in the Southwest w/ a trough over the east. Yeppers!

The 12z GEFS has flipped to an eastern trough. Look at it at 18z last night. Look at it now. @Holston_River_Rambler, thanks for the PDO numbers. It looks like it is trending away from severely negative. We just need it to get near neutral so it isn't default Mountain West trough.

As for the MJO, the CPC plots have it all over the place and all over the COD, but with very low amplitude. I can't find a single plot that gains amplitude. It is very difficult to find even a pattern among the cobwebs of plots. I think Jax's chi image from yesterday is pretty accurate. Six is going to fire-up for a few days, and then fade. There will be mild activity in the 8 region continuously. The signal gets washed out. I did think of this. Can anyone post the daily PDO graph (the one with the running line graph so we can see a trend)? I am going to get my run in for this AM and watch some CFB playoffs. I probably won't post about 12z until the last ensemble runs(EPS) around 2:30. I know some of you think when I don't post...it must have been a bad suite. Nope. Life just get in the way as it should! This is going to be a great football day.

I feel like the 6z AIFS Euro (which just ran) is a pretty good representation of the 0z EURO and GEPS. Temps under that gradually cool to seasonal or BN. It is again worth noting that seasonal temps can get the job done from mid-Jan to mid-Feb, provided that timing is works (meaning not warm-up and rain). But give me that setup - all day long. EPO ridge, AN heights over Greenland and AO regions, trough north(or east of Hawaii), split flow. Trends over the next 2-3 days will be important. For now, decent chance at a good pattern in the aforementioned timeframe.

Now, I do think the following is possible. We have seen it show up on modeling but without overall consistency ->The cold shot around the 12-13th rolls into the Plains and hangs up over the East. It could hang up over the Ohio river valley, the Tenn River valley, the Apps, or even the East coast. If/when it does, an over-running event seems plausible. Beware the cutoff low over the Southwest. They are tricky, tricky critters. On rare occasions, they will simply set-up shop per the deterministic GFS, spin for days, and just burn out. But IMHO, they kick out about 90% of the time. If it were to set up shop there, when it kicks...the trough should still come into the East. Pay me now or pay me later. The good thing I can see on modeling this morning is the EPO ridge is present. That has not changed. When it reaches into Point Barrow, a cutoff OR split flow could develop underneath it. I suspect we eventually see both - a cutoff/bowling ball and split flow. Details twelve days out are going to be sketchy. So, I started looking at individual 6z GEFS ensemble members - it is the ensemble of the worst case deterministic scenario. I am not done yet sifting through the other ensembles. The 6z GEFS is not as warm as I thought it would be. I scroll right on down to Jan13...and then 14th. Remember, those are BN temps during our coldest climatology. A good number of those troughs stall. That tells me the risk for over-running is very high. If I was sitting in middle and western Tenn...I would want to keep an eye on this, even E TN. I can't get individual 500 height panels for the US, so I resort to looking at the temp maps above. Below is the 500 mean map for the hour above. The individual members tell a different story. Many of them must have kicked the trough eastward as the SER is squashed on roughly 2/3 depending on your definition of "squashed." Many of those cold fronts stall somewhere over the East. Knowing that SW bias is possibly in play, we take that 500 map and run with it. The EPO ridge has blocking over the top. Below is the 12z trend map for Jan 12. It looks like that for the rest of the run which implies the ensemble is correcting eastward with the trough.

If you look at the 6z GEFS at 500, you can see a possible feedback loop start at 276....seems not realistic at all.

Model feedback has been a huge problem all winter. Honestly, I have never seen the over amplification this bad. Repetitive Baja lows, repetitive NW lows, and maybe now repetitive Four Corners lows. One low is generally plausible - if we start seeing slp reform over and over…that is more than likely feedback. I start tossing model runs at the hour that occurs. If we see the GFS correct to an eastern trough as we get closer…it will make me wonder.

I suspect we are seeing feedback over the SW which is a known issue w modeling. Now, an actuall cutoff low could be legit under that big EPO. That seems impossible to have a cutoff under the ridge, but it has happened before. But given the massive amounts of model feedback and infinite loops this winter, I suspect that trough kicks right on out. By ~Jan 12.

I think the GFS is out to lunch. It has been all winter. I guess a broken clock is right twice a day though, and I won’t discount it quite yet. It has some support from the 0z GEM, but the GEM ends before the transition on ~Jan12 is depicted on other modeling - the GEPS kicks the tucked in trough out of the West right after 240. Eastern trough looks on time on the 0z Euro, every nonGEFS ensemble suite I can find, and the AIFS Euro…even the AIGFS to some extent. The ensembles have not budged overnight…EPS, GEPS, AIFS Euro, AIGEFS. Roll with them at this range. Check ensemble member counts. As I noted yesterday, the main concerns are cold source regions and if the ridge continues to retrograde (doesn’t stop in the West or eastern PAC). It could be the MJO is trying to gain same amplitude…but it has been so inaccurate this winter I am not using it a ton - yet. When we switched to the chinook in late December, modeling projected the event to start right after the 10th. It took another 12 days before it actually showed up. I think the same thing is occurring here…just with the cold. If non-GEFS ensembles begin to move…that is worth paying attention to. GFS verification scores have been terrible of late.

The 18z AIGFS is straight up frigid. Let's continue to keep an eye on Jan 12th. If we can get that down to roughly 7 days, that may be a legit time to track something decent. That run had a decent snowstorm for middle and west. My main concern is this...if modeling, which has tended to under model cold fronts(exception Jan 2), then that cold could be stronger than shown.

I think it is also worth noting that NE TN and SW VA may well see some snow in the air tomorrow if the 18z RGEM is correct.

I am not convinced of the correlation between phase 6 and cold. What I think is occurring is QBO induced HL blocking(in some cases) is simply prevent the MJO signal from having influence over NA. I think the MJO has a much bigger impact when HL blocking is absent. As Cosgrove noted, the best thing we can do is simply look at the vortices lined-up which are approaching the US. You can kind of see the stormier patterns and deduce timing of such. Use analogs to fish out a good 500 pattern in addition to wx models. That is more accurate than relying on simply teleconnections which I am always guilty of...

So, when I look at that. I see an East African/IO wave working from 1-2 to 4-5 and then to 6(and then fizzling out). I also see some convection at the dateline which is phase 8. Looks like the phase 6 dies out. In my mind, that would correspond to the warm waves prior to the 12th per lagged composites? Looks pretty weakfish to me in general with 2-3 strong days in 6. I think HL blocking eventually trumps it unless it holds onto that stronger look for more than 2-3 days.

Pretty good looks in my book. I used to only do long range stuff based on precip anomalies and temp anomalies. I don't think I am much better today with all of the extra stuff. Here are some Euro LR ext maps centered on d15-46. I have attached both the mean and control runs. You can see below normal temps with above normal precip(yeah, that surprised me). I actually went through and looked at the precip by 7 day increments to see if it was just one big rainer. Nope, it looks like normal precip with the exception of the first maybe ten days. BN temps, AN precip, and a solid 500 map.

Thanks for that info. I was having a hard time reconciling what look like really cold maps with that phase. I know there are times when the MJO has less influence.