December 2017 Mid-Long Range Disco 2

[Cobalt]

12z EPS Vs 0z

0z:

Ridge looks far more suppressed

 

[Cobalt]

Cold

[Cobalt]

Ok, last post before I go to bed. Just saw that the EPS was good so I'm up.

Snowfall mean for EPS is REALLY good

Christmas would be cold according to the EPS

And finally, the potential of an event this Thursday has some support

Ok, I'm done. Just thought I'd post this stuff for anyone checking the forum in the morning

 

[mitchnick]

1 hour ago, Cobalt said:

Ok, last post before I go to bed. Just saw that the EPS was good so I'm up.

Snowfall mean for EPS is REALLY good

Christmas would be cold according to the EPS

And finally, the potential of an event this Thursday has some support

Ok, I'm done. Just thought I'd post this stuff for anyone checking the forum in the morning

 

Thanks Cobalt!  Great for us "ole' codgers" whose sleep habits are controlled by the mood of our prostates!

[MillvilleWx]

Man, I'm looking forward to seeing the GEFS after that run. That was actually a pretty solid overrunning event for these parts. Take the temps with a grain of salt at this point because the GFS loves to scour out CAD sigs too early. Verbatim, a 1036 high over NYS slowly progressing to the northeast would probably lead to a good, shallow cold airmass over the region with a plume of moisture attacking from the south. That's a snow to ice sig for sure. Would probably go over to rain for a time before wave 2 closes the door on a 3 day run of weather. Then a massive surface ridge in the Plains funnels down. SER was in a good spot, albeit a little further north comparing 0z. I think we're getting the feeling we're going to be playing the tightrope on where the baroclinic setup will eventually be placed. Bob is right on with this pattern. Going to be a long week leading up to Christmas me thinks. 

[CAPE]

13 minutes ago, MillvilleWx said:

Man, I'm looking forward to seeing the GEFS after that run. That was actually a pretty solid overrunning event for these parts. Take the temps with a grain of salt at this point because the GFS loves to scour out CAD sigs too early. Verbatim, a 1036 high over NYS slowly progressing to the northeast would probably lead to a good, shallow cold airmass over the region with a plume of moisture attacking from the south. That's a snow to ice sig for sure. Would probably go over to rain for a time before wave 2 closes the door on a 3 day run of weather. Then a massive surface ridge in the Plains funnels down. SER was in a good spot, albeit a little further north comparing 0z. I think we're getting the feeling we're going to be playing the tightrope on where the baroclinic setup will eventually be placed. Bob is right on with this pattern. Going to be a long week leading up to Christmas me thinks. 

Just saw that. Multiple wave, long duration deal. Cold nearby, and pressing. Been seeing variations of this for several runs now. Should be plenty of interesting runs ahead.

[CAPE]

Nice improvement in one model cycle-

[pasnownut]

6z says get out the Dramamine....cause its gonna be a rough ride in the sleigh around Christmas and beyond.  Lots to watch and it looks like we are in quite a battlezone.

Going to be interesting to see how this comes into focus.  Nice to see the Euro south with the trough....

Nut

[AfewUniversesBelowNormal]

Not much cold air now.. maybe that will change

[Wonderdog]

3 hours ago, Cobalt said:

Even stronger signal for an event Friday. Maybe not much, but an event possibly

At 6z, that Friday event misses us to the north on the GFS but it is closer to us than the 0z GFS.

[Wonderdog]

 

 

 

Somewhat closer. But things are developing nicely in the southern states!

 

[AfewUniversesBelowNormal]

I mean, verbatim 06z GFS ensembles now almost -PNA. Almost the worst with +NAO too, but it likely won't verify. GOA ridge becomes -AO or resets way way west with then GOA low. Because of 10mb warming, I think it's -AO 

[BristowWx]

6z looks like the heartbreak ridge solution to me compared to 0z which picked up on the CAD just fine.  Op run so won't get too worked up.  Good morning everyone.

[AfewUniversesBelowNormal]

This is like... there's no cold air though. The whole pattern is driven by +ridging. Do models not take this into account? 

[showmethesnow]

Going over the runs last night and I am no closer to having a clue as what to expect for the Christmas period of time. In fact the period after Christmas is probably an easier call to make. At this point it looks as if we will be dealing with a SW trough through that period and it will all come down to how much interaction we see between that feature and surges of the trough coming down from Canada. Just little differences there will have huge impacts downstream through our neck of the wood. So flip a coin on what to expect.

Now as far as after Christmas? The GEFS and the EPS seem to be quickly locking onto a solution AND WOW!!!! Now maybe there will be some that disagree with me but that look they are starting to lock into has my Snow Weenie senses tingling. The look is one of possible high impact storms through our general region. And the best part? The setup looks to be for an extended period of time. And it is all thanks to the SW trough many of have been cursing for awhile now. Let's throw up some maps to give you an idea what I am talking about.

Now I could have picked just about any hour shortly after Christmas because this look extends all the way through the end of the run. But this is just a snap shot of 300 hr at 500 mb. What we see is ridging and higher pressures running into Alaska. The black line running over top of it dropping down into the CONUS and then trough our region is roughly where we will see the NS flow. Now below the ridging we see troughing/lower pressures extending a good deal into the Pacific off of S Cal and the Bajas. What this is doing is creating a split flow. So what we see is a SS that is under cutting the SW troughing running through Mexico and then through the SE US. Now the purple E's are just an illustration of possible energy that we will see embedded within both of these flows at any given time. The purple circle is where we see the chances of possible phasing between these two streams any energy embedded within them can possible occur. Notice that it is quite an extensive area for possible phasing from the central US to off the east coast. The best part is we have blocking to the north, created by the PV, of these streams which limits any phasing systems northward movement as the system amplifies. So in a nutshell, no matter where we see a possible phase occur, chances are much higher that we don't see a system cut to our west then what we would typically see with a farther western phase.

 

 

 

Now again I could have used any hour to show the jets at 250 mb but for consistency I will the 300hr below. Now notice we have the polar jet to the north riding over the Alaskan ridging diving into the CONUS where it is riding over top/merging with a tropical jet that is undercutting the trough extending off of Baja/S Cal. So we have very cold temps being driven southward into the CONUS by the polar jet and warm moist air being driven through the southern states by the tropical jet. Also notice that we are seeing this converging in the central US. Again this gives us much more play with possible phasing. Needless to say this is a very good setup for our region.

 

 

Now I mentioned that I was just taking a snapshot in that period of time. Well here is the 5 day extending back from the end of the run. Notice not much difference at all.

 

Now here is the 5 day temp profile for that same 5 day period. That temp profile is sweet. It implies that the boundary for any possible storm would set up roughly in southern Va for our region. Which is a prime spot for snow chances DC/Balt. Wanted to also mention that through this period of time we see high pressure locked into our northwest which is another key ingredient for our snow chances and is also quite often found with our bigger snows.

 

To further elaborate on the possible setup in the extended. I basically discussed possible bigger ticket items with phasing. But this setup has far more potential then that. We could see a solely NS driven storm which is possibly able to tap into tropical moisture to its south producing a moderate event. We could also see just general over running induced by the southern jet throwing moisture over top of the cold air dome in place again producing a potentially moderate event. Now we see this setup immediately after Christmas through the end of the run where the models tend to attempt to break down the SW trough. So roughly a week. But from what I have seen with the models in attempting to pull that trough out they continue to delay that process, kicking that can down the road. So I would not be surprised that in fact we see this general setup continue beyond the end of the run, possibly for a somewhat extended period of time afterwards. 

Again, some may not agree with me, but this look if it comes close to verifying in my mind has the potential to rival some of the best stretches of snow we have seen in recent memory.

Now I can't stress this enough. The models can and do change so this is not set in stone. That being said, from what I have seen with the last few days of models runs I think this is of a higher probability of verifying then what we typically see with +10 day forecasts.

eta: Just wanted to add, we have seen the models starting to hit on the snowfall totals for shortly after Christmas. If my thoughts on that period of time have any legs we will probably see some massive increases in the snowfalll means showing up in the coming days.

 

[Wonderdog]

19 minutes ago, showmethesnow said:

Going over the runs last night and I am no closer to having a clue as what to expect for the Christmas period of time. In fact the period after Christmas is probably an easier call to make. At this point it looks as if we will be dealing with a SW trough through that period and it will all come down to how much interaction we see between that feature and surges of the trough coming down from Canada. Just little differences there will have huge impacts downstream through our neck of the wood. So flip a coin on what to expect.

Now as far as after Christmas? The GEFS and the EPS seem to be quickly locking onto a solution AND WOW!!!! Now maybe there will be some that disagree with me but that look they are starting to lock into has my Snow Weenie senses tingling. The look is one of possible high impact storms through our general region. And the best part? The setup looks to be for an extended period of time. And it is all thanks to the SW trough many of have been cursing for awhile now. Let's throw up some maps to give you an idea what I am talking about.

Now I could have picked just about any hour shortly after Christmas because this look extends all the way through the end of the run. But this is just a snap shot of 300 hr at 500 mb. What we see is ridging and higher pressures running into Alaska. The black line running over top of it dropping down into the CONUS and then trough our region is roughly where we will see the NS flow. Now below the ridging we see troughing/lower pressures extending a good deal into the Pacific off of S Cal and the Bajas. What this is doing is creating a split flow. So what we see is a SS that is under cutting the SW troughing running through Mexico and then through the SE US. Now the purple E's are just an illustration of possible energy that we will see embedded within both of these flows at any given time. The purple circle is where we see the chances of possible phasing between these two streams any energy embedded within them can possible occur. Notice that it is quite an extensive area for possible phasing from the central US to off the east coast. The best part is we have blocking to the north, created by the PV, of these streams which limits any phasing systems northward movement as the system amplifies. So in a nutshell, no matter where we see a possible phase occur, chances are much higher that we don't see a system cut to our west then what we would typically see with a farther western phase.

 

 

 

Now again I could have used any hour to show the jets at 250 mb but for consistency I will the 300hr below. Now notice we have the polar jet to the north riding over the Alaskan ridging diving into the CONUS where it is riding over top/merging with a tropical jet that is undercutting the trough extending off of Baja/S Cal. So we have very cold temps being driven southward into the CONUS by the polar jet and warm moist air being driven through the southern states by the tropical jet. Also notice that we are seeing this converging in the central US. Again this gives us much more play with possible phasing. Needless to say this is a very good setup for our region.

 

 

Now I mentioned that I was just taking a snapshot in that period of time. Well here is the 5 day extending back from the end of the run. Notice not much difference at all.

 

Now here is the 5 day temp profile for that same 5 day period. That temp profile is sweet. It implies that the boundary for any possible storm would set up roughly in southern Va for our region. Which is a prime spot for snow chances DC/Balt. Wanted to also mention that through this period of time we see high pressure locked into our northwest which is another key ingredient for our snow chances and is also quite often found with our bigger snows.

 

To further elaborate on the possible setup in the extended. I basically discussed possible bigger ticket items with phasing. But this setup has far more potential then that. We could see a solely NS driven storm which is possibly able to tap into tropical moisture to its south producing a moderate event. We could also see just general over running induced by the southern jet throwing moisture over top of the cold air dome in place again producing a potentially moderate event. Now we see this setup immediately after Christmas through the end of the run where the models tend to attempt to break down the SW trough. So roughly a week. But from what I have seen with the models in attempting to pull that trough out they continue to delay that process, kicking that can down the road. So I would not be surprised that in fact we see this general setup continue beyond the end of the run, possibly for a somewhat extended period of time afterwards. 

Again, some may not agree with me, but this look if it comes close to verifying in my mind has the potential to rival some of the best stretches of snow we have seen in recent memory.

Now I can't stress this enough. The models can and do change so this is not set in stone. That being said, from what I have seen with the last few days of models runs I think this is of a higher probability of verifying then what we typically see with +10 day forecasts.

eta: Just wanted to add, we have seen the models starting to hit on the snowfall totals for shortly after Christmas. If my thoughts on that period of time have any legs we will probably see some massive increases in the snowfalll means showing up in the coming days.

 

Very interesting write-up Showme. I just wish this was 8 days out as opposed to 10+. LOL

[Scraff]

@showmethesnow kicking off my Saturday the right way! Great write and explanations. Seems like we should start seeing some long range threats start dialing in soon?

[showmethesnow]

7 minutes ago, Wonderdog said:

Very interesting write-up Showme. I just wish this was 8 days out as opposed to 10+. LOL

Could have elaborated further but the above post was wordy enough as it was. There are a couple of things that make me think that what the models have in the extended may be the real deal. First we have seen the models hinting on and off with the possibility of this type of setup for quite awhile now. These hints have grown over the last few days and now I think the models are finally latching onto it somewhat strongly. This is a good indication in my mind that the models are feel that the large scale features argue this is how the pattern should evolve. Another thing that has my confidence building is related to a post I made several days ago in regards to the SST temps we see off of Baja. We continue to see temp drops with that cold pool off of Baja and now we are also seeing those temp drops increasing in area. The location of these drops are almost spot on with what the models are now showing in regards to the trough/lower pressures which have a tendency to gravitate to the colder waters. North of that we are seeing warm SST anomalies running up the west coast which are for the most part holding on strong. These argue for ridging and higher pressures running up into Alaska. This configuration of SST temps argues strongly for what the models currently show in the extended @ 500mb with ridging extending into Alaska and that being undercut by troughing. Basically a split flow. So like I said, though things can and do change with the models, I think from what I am currently seeing they argue for this setup and thus why I have a higher confidence level then I would typically have with a 10+ day model run.

[packbacker]

7 hours ago, Bob Chill said:

You know...hypothetically...with the way the pattern looks in general, there very well could be multiple waves running along the back of a se ridge that produce multiple rounds of snow over a multiple day period. Sorta like a warmer version of jan/Feb 2015 in Boston. 

Nice!  4" mean this far out on the EPS is really impressive.  Could be snowy several days for you guys.  

[poolz1]

Great writeup @showmethesnow.  I completely agree with your thoughts on the extended...there will be big time cold around and there seems to be a very good consensus than the boundary will be south of us after the holidays...before the holidays is still a bit up in the air.  Gonna be some fun tracking ahead!

On a side note...today's SOI came in at -19.10  MJO on the move?

[Chris78]

Awesome write up showmethesnow. Always enjoy reading your posts/view points.

[showmethesnow]

24 minutes ago, Scraff said:

@showmethesnow kicking off my Saturday the right way! Great write and explanations. Seems like we should start seeing some long range threats start dialing in soon?

Thank you.

Really haven't looked into the snowfall maps too hard but by just looking at the means response we are probably already seeing some nice hits in the extended by a few members. If my thoughts have a validity (fingers crossed) I think we should start seeing more and more members latching onto that period and quickly to boot. So don't be surprised over the next couple of days we see some incredible jumps on the means through that period of time.

[showmethesnow]

5 minutes ago, Chris78 said:

Awesome write up showmethesnow. Always enjoy reading your posts/view points.

Thanks.

One other thing I did want to mention and failed to before. If we see the models move quicker to the look in the extended, with the trough farther south and west extending to off the Baja, it will most likely positively impact the the period of time around Christmas. But that one is a hard one to call at this point. It is just as likely to delay that progression as to speed it up. Still basically a coin toss in my mind.

[showmethesnow]

14 minutes ago, poolz1 said:

Great writeup @showmethesnow.  I completely agree with your thoughts on the extended...there will be big time cold around and there seems to be a very good consensus than the boundary will be south of us after the holidays...before the holidays is still a bit up in the air.  Gonna be some fun tracking ahead!

On a side note...today's SOI came in at -19.10  MJO on the move?

Thank you.

I haven't had this much fun tracking in quite a few years. Here's hoping that we are doing this through March.  

[Chris78]

6 minutes ago, showmethesnow said:

Thanks.

One other thing I did want to mention and failed to before. If we see the models move quicker to the look in the extended, with the trough farther south and west extending to off the Baja, it will most likely positively impact the the period of time around Christmas. But that one is a hard one to call at this point. It is just as likely to delay that progression as to speed it up. Still basically a coin toss in my mind.

I think it's a toss up on wether the cold makes it here by Christmas but I think the days after Christmas leading into New years  weekend is loaded with potential.

[osfan24]

Bernie seems bullish and on board for this far out.

 

 

[clskinsfan]

Last nights Euro run has the look of a big mountain snow storm. It is a long ways out but I love being on the northern fringe at this range. 

[RDM]

25 minutes ago, osfan24 said:

Bernie seems bullish and on board for this far out.

 

 

Can't read the quote in your post.  If not feasible to change the background color, can you please quote the text and link separately?  Thanks  (edited for typo)

[poolz1]

EPS for FDK....showing the waves of qpf thru the period and which waves could be frozen.

[gopper]

As a "Post less, Read more" participant of this forum, I want to give my sincere appreciation to those who have the knowledge and the ability to share insight in a manner that is understandable and fruitful to others reading.  As a teacher, I appreciate those who make complicated atmospheric maps and concepts easier to understand.  Posters like @showmethesnow, @Bob Chill, @psuhoffman, @mitchnick, @usedtobe and many other red taggers and hobbiest are the reason I find much pleasure in this weird hobby.  The fact that meteorology is an inexact science keeps me intrigued much like an old man playing slots for hours at a time.  So, thank you to all of those people who make this hobby so much fun.  Oh, and a special thank you to Mr. Cold Meiser who is seemingly beating his brother up so far this year in the Mid-Atlantic.