January 2021 Medium/Longterm Pattern Discussion.

[AMZ8990]

January Discussion thread, figured it was time to start one given how close we are to the new year.

[nrgjeff]

Nice timing! Strato Warming has apparently ingested into the just released ECMWF weekly charts. I approve that message!

Greenland block remains stout for 3-4 weeks. Some ridging West Coast. North Pac trough is more Bering sea than Alaska, a bullish shift for here.

Surface Deep South is blue. Tennessee Valley and Mid South is variable. However these next four weeks are the core of January. We take!

I'll be off for a few days. Merry Christmas!

[John1122]

Haven't been looking past this storm other than the eye popping Euro run. I do see that the teleconnections are basically perfect the first several days of January. Super negative AO. Moderately negative NAO. Somewhat positive PNA.  Those scream cold and winter storms here. Heck, I'm already close to 7 inches for the season and it's only December 24th. Barring a massive collapse (which is highly possible) I may get my average of around 16-17inches. Though lately I either have a 20-30+ inch season or I have 5 or 6 inch seasons. 

[Wurbus]

Looked to me that the Euro still had the system, just after New Years, in the gulf; but it got suppressed this run and fizzled out.

[Holston_River_Rambler]

Yeah, it just gets shredded by the bigger storm earlier, when that storm hits the big block and gets stuck. 

0z overnight/ 12z yesterday (side by side, no less, a la Carver)

 

 

I think with the Pac jet extension caused by the big Siberian high, having the zonal look from overnight is gonna be a risk until the jet snaps back after that extension. it's like a conveyer belt of energy getting cranked up and spitting out energy that has to be timed just right with the big NAO block. About the same number of EPS members have a storm around that time though, as compared to the 12z run, so something is still possible in that window. 

The 6z GFS (it's Christmas, so why not) shows a positive outcome to what might happen as the jet retracts:

 

Some of the bad convection areas looking fiesty right now too:

 

The 3D Strat vortex looking rough, so that can't be anything but good. No big split guaranteed and like others have said, no telling exactly how that would turn out, but so far it being under stress seems to have been good:

 

Ensembles:

[Carvers Gap]

LR thoughts...posted them in the Dec thread but will link them here in the new thread.  Changes in global ensembles (2 posts)....

 

[Carvers Gap]

And just like that the GEFS and GEPS are back to a workable look at 12z.

[Holston_River_Rambler]

EPS too

[Carvers Gap]

25 minutes ago, Holston_River_Rambler said:

EPS too

That is how it should look.  That is better than good.  As a friend noted, a ridge may roll through from time to time...but that is how a block should look.  Not sure I have a seen a block that intense last for that long.  Yesterday's system of cold catching rain was old school.  That look right there is old school.  I think modeling is feeling that unfavorable MJO, but the very favorable -NAO is balancing this Sith/Jedi pattern in the LR - where there is one, there is another.  Well, something like that...

[Holston_River_Rambler]

For some reason the full gif didn’t load. The end looks even better! Some PNA action. 

[Carvers Gap]

1 hour ago, Holston_River_Rambler said:

For some reason the full gif didn’t load. The end looks even better! Some PNA action. 

What would be gold would be to have the TPV split, head south, and get locked under that block right there.  

[Carvers Gap]

18z GFS with "Cold Catching Rain Sequel" on NYE. LOL.  That would make like three times that has happened in a month.  Old timers around here used to tell me when I was little that often the best snows came immediately after heavy rain during the winter.  This has been an "old school" month for weather:  -NAO, cold catching the rain, and an early start to winter.  

[Carvers Gap]

I like this map from the CFSv2 for January.  It looks a lot like the Weeklies Canadian which came out last night.  I think there will be times when a trough rolls through and after that a ridge rolls through and maybe connects to the -NAO.  That, in turn, will create some nice weather at time’s.  However, one thing which seems like a constant is this look.  Sometimes it has the small ridge out west and sometimes it doesn't.  This pattern looks remarkably similar to the set-up which just produced this current storm.  Going to see some cutters with that look.  Likely will see some coastals if it verifies.   This is the kind of pattern that has an outside chance of opening the Arctic, letting cold slide south, and then trapping it under that ridge.  That happens at times.  Right now, afternoon ensembles have a +PNA, -NAO,- and -AO.  Get some normal temps into the SE for January, and we might have some more chances.  You can pretty much see the storm track on that map.  Verbatim, that wold give our folks in the western sub-forum some chances as well.  Those tracks would have some cutters, sliders, and coastals. Needs some cold in that pattern for things to be really good, but that map is workable...not exceptional but workable.

[Wurbus]

Round 2 on the GFS next week on NYE. Looks almost identical to the recent snowfall but gets more of the state involved.

[Save the itchy algae!]

The 6z GFS has a monster in five days.

[Holston_River_Rambler]

6z GFS OP would be an ideal solution FMBY. The energy digs south and progresses through our longitude in a great way:

If you've heard people say, "you have to get cold air and moisture to meet," this is a great way to get it. That NW to SE tilt the energy takes, helps throw that moisture back over the cold air.

6z GEFS (new version) more enthused for western areas, but still a lot of misses for everyone. Old 6z GEFS has some nice hits too.

 

The UMKET has a really deep piece of energy that digs further south, but it turns negative too far west:

 

The CMC and Euro are in the middle of these two. But I would say closer to the Ukie. Hopefully, if a similar set up happens again this week, western areas can benefit this time. EPS says nada. 

 

[Save the itchy algae!]

By mid week we will have another significant storm system headed our
way.  Slowed down approach of POPs by 6 hours in the grids, based on
new Euro run with deeper trough and slower movement.  We should have
a classic setup for a 12-18 hour Mountain Wave Wind event centered
right now around Thursday, with the timing differing in models. The
low level winds will be bringing up a lot of moisture, thereby
inducing some instability.  Have kept Thunder out for now, but could
see it possibly getting into southern parts of the area Thursday.

On the back side of this system the colder air could offer another
chance of snow around Thursday night into early Friday.  The overall
scenario is not too different from this White Christmas scenario,
but too early to know about available moisture, how quickly airmass
will cool, and how much lift there will be.  Looks like this precip
will taper off pretty quickly around Friday.

Edit: sorry guys, don’t know why the font is so large.

[Kasper]

47 minutes ago, Save the itchy algae! said:

By mid week we will have another significant storm system headed our
way.  Slowed down approach of POPs by 6 hours in the grids, based on
new Euro run with deeper trough and slower movement.  We should have
a classic setup for a 12-18 hour Mountain Wave Wind event centered
right now around Thursday, with the timing differing in models. The
low level winds will be bringing up a lot of moisture, thereby
inducing some instability.  Have kept Thunder out for now, but could
see it possibly getting into southern parts of the area Thursday.

On the back side of this system the colder air could offer another
chance of snow around Thursday night into early Friday.  The overall
scenario is not too different from this White Christmas scenario,
but too early to know about available moisture, how quickly airmass
will cool, and how much lift there will be.  Looks like this precip
will taper off pretty quickly around Friday.

Edit: sorry guys, don’t know why the font is so large.

Don’t you scream at us! Lol

[Kasper]

2021 says “hold my beer”

[Save the itchy algae!]

Don’t make me break out the CAPS LOCK.

[Carvers Gap]

The CFSv2 seasonal(which bounces around and changes quite a bit as it runs once per day) illustrates the concern for January, and also illustrates how a -NAO can create a ridge in the East.  I think we will see an undetermined period of the look below - might be just a few days, a week, or weeks.  Just tough to tell.  We are now entering that time frame that is one where I have low confidence as modeling is juggling several plates(see my posts yesterday).  The GEFS OLR maps today do depict convection in the IO(Inidan Ocean) region in the phases 3-4 regions and maybe some weaker convection in the phases 1-2 regions as well.  We don't want that showing up long term as one only needs to look to last winter to see the consequences of that.  The run below kind of shows what modeling is dealing with.  The 0z EPS now has a similar look to what is below.  The variability is possibly due to the MJO becoming possibly becoming more of a factor on some modeling and even during various model runs...and less on others.  What all of this means is that the Atlantic(-NAO) is going to have to be the driver in the LR if we want more cold and snow after the New Year and little help from the Pacific is on the Horizon....and the Atlantic, if too strong, can actually become a thorn as well.  Finally, let's see where the EPS goes(the 6z GEFS implies the ridge).  I don't like losing it in the LR.  Just one run of the EPS which looks bad, so let's see where it goes.

Indeed, the 6z GFS has a similar set-up to the Christmas Eve event.   The Euro is basically a cutter for that event.  CMC is in between the Euro and GFS.  Canadian modeling has been pretty good this winter.  The window from NYE to maybe around Jan 4th has some potential for the subform.  After that time frame...toss-up.

[Carvers Gap]

As for the 6z GFS, going to need other modeling come east as the GFS is on the eastern side of the envelope (and trended westward at 6z) for the NYE storm.   Still a long way to go on that one.  We were fortunate to track the Christmas Eve deal from almost ten days - that is a rarity.  The pattern does support 1-2 storms taking the low road during that time frame.  The storm immediately after the NYE storm is kind of what I am watching.  

[Carvers Gap]

I think anytime we have a strong fold front on modeling (during the next couple of weeks), going to have to be watched.  

[Carvers Gap]

Just digging through modeling this morning.  Here is the 6z Euro Control.  @Holston_River_Rambler, I don't think the operational goes out to 144 and neither the ensemble nor deterministic have precip types at 6z, right?  Either way, this is a good look eastern section of middle TN and mirrors the 6z GFS.

 

[1234snow]

12z GFS is BIG for middle TN. Foot+ in some spots up to 20 inches in Eastern KY

[Carvers Gap]

My only concern with the GFS is how quickly it is moving its snow axis westward.  During the last four runs, it has moved from eastern W VA to Lexington, KY, at that latitude.  Would be nice to see it settle on a track.   Let's see where the CMC goes.

[Carvers Gap]

The fly in the ointment with this storm is the high near Bermuda is not getting out of the way.  It is creating return flow over the SE.

[Carvers Gap]

12z CMC has snow in Kansas.  True cutter.

[Daniel Boone]

2 hours ago, Carvers Gap said:

The CFSv2 seasonal(which bounces around and changes quite a bit as it runs once per day) illustrates the concern for January, and also illustrates how a -NAO can create a ridge in the East.  I think we will see an undetermined period of the look below - might be just a few days, a week, or weeks.  Just tough to tell.  We are now entering that time frame that is one where I have low confidence as modeling is juggling several plates(see my posts yesterday).  The GEFS OLR maps today do depict convection in the IO(Inidan Ocean) region in the phases 3-4 regions and maybe some weaker convection in the phases 1-2 regions as well.  We don't want that showing up long term as one only needs to look to last winter to see the consequences of that.  The run below kind of shows what modeling is dealing with.  The 0z EPS now has a similar look to what is below.  The variability is possibly due to the MJO becoming possibly becoming more of a factor on some modeling and even during various model runs...and less on others.  What all of this means is that the Atlantic(-NAO) is going to have to be the driver in the LR if we want more cold and snow after the New Year and little help from the Pacific is on the Horizon....and the Atlantic, if too strong, can actually become a thorn as well.  Finally, let's see where the EPS goes(the 6z GEFS implies the ridge).  I don't like losing it in the LR.  Just one run of the EPS which looks bad, so let's see where it goes.

Indeed, the 6z GFS has a similar set-up to the Christmas Eve event.   The Euro is basically a cutter for that event.  CMC is in between the Euro and GFS.  Canadian modeling has been pretty good this winter.  The window from NYE to maybe around Jan 4th has some potential for the subform.  After that time frame...toss-up.

The good thing about that is generally a ridge extending from Greenland all the way to the SE occurs during the warm seasons. It's keying on trough Nw pendulum ridge SE. I  Remember in 95-96, troughs going n2 NW along with strong Greenland blocking and that scenario never happened. Although, a semblance of a SE Ridge would try to pop in conjunction , i.e., short mild flooding periods that winter as cutters shot up between the 2.. of course, the dreaded Hi Amp Warm phases MJO could possible cause that config..

[Carvers Gap]

9 minutes ago, Daniel Boone said:

The good thing about that is generally a ridge extending from Greenland all the way to the SE occurs during the warm seasons. It's keying on trough Nw pendulum ridge SE. I  Remember in 95-96, troughs going n2 NW along with strong Greenland blocking and that scenario never happened. Although, a semblance of a SE Ridge would try to pop in conjunction , i.e., short mild flooding periods that winter as cutters shot up between the 2..

Saw a post on another forum(maybe MA), where the strat warm stuff may be causing some of this for early January modeling.  Seems like 2-3 winters ago, we had a January that looked great on LR modeling, and the strat warm pretty much wrecked havoc on that.  Makes me wonder if we are about to see large scale changes(could be really good or the opposite) after mid-January.  The SSW could have a hand in that look as well.  

Ah, I remember now(forgive the stream of thought post!)...the MA referenced a tweet about the eastern US being warmer than normal during the events leading up to a strat warm.   LOL- heck, I have even talked about it, but always forget when it happens in modeling.   When there is a massive ridge along the east coast of NA(basically a WAR on steroids...talking like Cuba to Greenland), that has preceded the last 2-3 SPV splits.  

Have to admit, I am not excited about this strat split scenario...but it does open the door for very cold air(due to the NAO) to enter the east after the split.  Just going to depend on which side of the globe the coldest air goes.