Winter 2021/22 December Thread

[Carvers Gap]

12z CMC is better in terms of the pattern here.  Snow on the 3rd and then a cold period follows.  

[AMZ8990]

If you guys have time, go to weather.gov and check out the winter storm warnings on the US map that’s on the homepage.  The entire west coast from Northern California all the way up to south Washington state is under a winter storm warning.  It’s crazy to see how many areas could see measurable snow between now and Monday out that way.  Just a massively wide swath of winter weather.  

[AMZ8990]

17 minutes ago, Carvers Gap said:

12z CMC is better in terms of the pattern here.  Snow on the 3rd and then a cold period follows.  

Brutal cold if that verifies.  Most of the country is at or below freezing at the end of that run.  January is starting to look more interesting by the day.  Merry Christmas to everyone, hope you and your families have a blessed holiday season.  @jaxjagman praying for your speedy recovery my friend.

[jaxjagman]

WOW !! @ THE SOI

 

25 Dec 2021	1015.80	1003.15	46.34	10.90	10.65
24 Dec 2021	1014.85	1005.50	29.22	10.18	10.14
23 Dec 2021	1011.50	1006.15	8.46	9.60	9.63
22 Dec 2021	1009.09	1007.85	-12.87	9.60	9.34
21 Dec 2021	1009.99	1011.50	-27.14	10.36	9.37
20 Dec 2021	1011.33	1009.50	-9.81	11.50	9.67

[Carvers Gap]

1 hour ago, jaxjagman said:

WOW !! @ THE SOI

 

25 Dec 2021	1015.80	1003.15	46.34	10.90	10.65
24 Dec 2021	1014.85	1005.50	29.22	10.18	10.14
23 Dec 2021	1011.50	1006.15	8.46	9.60	9.63
22 Dec 2021	1009.09	1007.85	-12.87	9.60	9.34
21 Dec 2021	1009.99	1011.50	-27.14	10.36	9.37
20 Dec 2021	1011.33	1009.50	-9.81	11.50	9.67

That is Nino level, right?  Like strong Nino?  Would also be indicative of a pattern flip over NA pending I think.  That is craziness.  What is your take on that, Jax?

[Carvers Gap]

The 12z EPS is much cooler through 300 than it was at 0z, and 0z was not too shabby.

[Carvers Gap]

The 0z Euro control, which has kind of been leading the ensemble for the past few days, is quite cold after the 3rd.  "Bitterly" might be too strong of a word....but it is headed there.

[Carvers Gap]

The 12z EPS is now very close to being in that CMC camp from a few days ago.  Good trends.  ALWAYS wary of the rug being pulled out...but seeing BN temps at the time when it is climatologically coldest is cold indeed.  

[Holston_River_Rambler]

I think the big +SOI jump is more Ninaish, but that is partly due to a TC basically sitting on top of Darwin:

 

It may fall back off after that TC moves off to the east. 

[Carvers Gap]

One potential we may see 

9 minutes ago, Holston_River_Rambler said:

I think the big +SOI jump is more Ninaish, but that is partly due to a TC basically sitting on top of Darwin:

 

It may fall back off after that TC moves off to the east. 

Went and looked it up.  Below -8 is El Nino.  Above +8 is La Nina according to BOMM.  So, basically we have been in an El Nino SOI state( @John1122all over that) and now we are returning to a Nina(edit) state.  That jump is going to create a shift downstream.  

Just looking at ensembles.  Looks like the trough just goes nuts over the East for about 7 days beginning on the 3rd.  Looks like that is decent window for storms if the STJ will stay as active as it looks.  Then, potentially the trough lifts out....not convinced that is actually what happens but it could.

[Holston_River_Rambler]

Merry Christmas y'all! 

Here's some ensemble gif presents

GEFS:

 

EPS

 

GEPS:

 

FWIW I think the reason the GEPS and GEFS have more of a SE ridge late in the run, is because they lose the -NAO. Hopefully that feature will prove more stubborn.  

 

 

 

 

[jaxjagman]

4 minutes ago, Holston_River_Rambler said:

I think the big +SOI jump is more Ninaish, but that is partly due to a TC basically sitting on top of Darwin:

 

It may fall back off after that TC moves off to the east. 

Yeah this causes the Walker Circulation to strenghten,and causes upwelling in the Eastern Pac,basically you can see the waters cooling now in the east to the surface

[jaxjagman]

6 minutes ago, jaxjagman said:

Yeah this causes the Walker Circulation to strenghten,and causes upwelling in the Eastern Pac,basically you can see the waters cooling now in the east to the surface

Tried to find a decent map,but here is one

[Carvers Gap]

16 minutes ago, Holston_River_Rambler said:

Merry Christmas y'all! 

Here's some ensemble gif presents

GEFS:

 

EPS

 

GEPS:

 

FWIW I think the reason the GEPS and GEFS have more of a SE ridge late in the run, is because they lose the -NAO. Hopefully that feature will prove more stubborn.  

 

 

 

 

Looks like the Aleutian ridge weakens more on the 12z EPS.  Great thing is I think the EPS is getting into the part of the season where it is a bit more trustworthy - maybe. LOL.  Operationals are very cold.  Trends are good right now in regards to the Aleutian ridge.  The GFS has been leading its ensemble for a few days....and it is a total pattern flip.  For now, looks like a decent window for winter wx between the 3rd and 10th.   Could definitely change as that is still a ways out there....key is the weakening of the Aleutian ridge.  That SOI bump may do the trick.  Do you have the gifs for the 12z operationals handy?

[Carvers Gap]

All three 12z global operationals reverse the current pattern over the lower 48 in one form or another...and especially off SW Alaska.

The Aleutian ridge is currently digging a downstream western trough which is forcing a SE ridge.  The weaker that Aleutian ridge after Jan 1, the weaker that SER and the more the cold pushes.  Everything hinges on that ridge being displaced, removed, or weakening.

The bigger development is seeing the GFS pop a +PNA.  Euro has something similar at 240 with ridging building out West.  Canadian just puts all of NA in the icebox.  

[Mr. Kevin]

Merry Christmas guys! Sorry jax for being dumb with this question but what is so exciting about the soi? Lol. Everyone seems excited about it. Just confused 

[Holston_River_Rambler]

8 minutes ago, Carvers Gap said:

Do you have the gifs for the 12z operationals handy?

 

GFS:

 

CMC:

 

Euro:

 

And the extended control, just for good measure:

 

[Carvers Gap]

Anytime, the SOI jumps like that...usually a big shake-up ensues downstream.   Also is true in reverse.  Things start moving.  We don't want the SOI in strong El Nino territory.  

1 minute ago, Holston_River_Rambler said:

 

GFS:

 

CMC:

 

Euro:

 

And the extended control, just for good measure:

 

Santa brining the goods(meaning the gifs).  Thank you!!!!

[Carvers Gap]

Not Jax or Holston, they are the SOI gurus...but when you see the SOI move like that....all kinds of movement occurs regarding hemispheric flow.  IMHO, usually means a sharp pattern change would be under way.  Now, we may or may not like the end result of that pattern change, but that is usually a signal of things switching up.

[Carvers Gap]

3 minutes ago, Holston_River_Rambler said:

 

GFS:

 

CMC:

 

Euro:

 

And the extended control, just for good measure:

 

The BIGGEST thing I thought was interesting....watch the Aleutian ridge on all three of those operationals.  What do you all see?

[Mr. Kevin]

1 minute ago, Carvers Gap said:

Not Jax or Holston, they are the SOI gurus...but when you see the SOI move like that....all kinds of movement occurs regarding hemispheric flow.  IMHO, usually means a sharp pattern change would be under way.  Now, we may or may not like the end result of that pattern change, but that is usually a signal of things switching up.

 

Just now, Carvers Gap said:

The BIGGEST thing I thought was interesting....watch the Aleutian ridge on all three of those operationals.  What do you all see?

I see I see I see Santa staring at me lol

[jaxjagman]

5 minutes ago, Mr. Kevin said:

Merry Christmas guys! Sorry jax for being dumb with this question but what is so exciting about the soi? Lol. Everyone seems excited about it. Just confused 

It should help with a pattern change upcoming,to what extent i have no clue

[Carvers Gap]

Really, because we cannot see past the 10th...can't be sure if this is a pattern change or just the PNA relaxing as a result of the Aleutian ridge weakening.  The Aleutian ridge could restrengthen.  We need the current block to reconfigure just enough to allow the buckle in the western jet to swing forward.  That either is going to have to happen with a weakening of the ridge in the Pac OR (and this may seem counterintuitive and may even be an error in my thinking) a slight weakening of the NAO.  I have been watching this very several days.  When the NAO weakens just a bit, the trough kicks eastward.  Only problem, it lifts right out with no block in place.  So, we need the NAO to weaken just enough to allow the trough to slide underneath, but get get blocked and not allowed to scoot out.  That may we an error in my part....but that NAO needs to soften up just a bit.  But.... we still need it.  AO may be the driver going forward.

[Mr. Kevin]

I would like to see a lengthy Pacific shakeup or whatever it takes to get it better and favorable for cold and occasional storminess here

[jaxjagman]

7 minutes ago, Mr. Kevin said:

Guess we'll see. A little cooler behind a cold front isn't a pattern reversal imo. A shift in the alutian ridge based on where it's been for a while now is. Just my 2 cents

Dunno,i'd like to see the GEFS side with the GFS.But they are complete opposite.So this could be a death ridge just as well

[Carvers Gap]

I suspect we fight that Aleutian ridge all winter...There is a reason people out West absolutely love La Nina winters.  Weak La Nina winters here(southern Apps) can be very cold at times(maybe even as a general rule), but not always.  People on the EC don't like La Nina winters.  West of the Apps it can work.  We don't need super cool weather in early January to have a chance.  Just need seasonal.  Right now if forced...I would way the trough lifts out around the 10th.  However, what happens after that is really open for debate.  Does the Pac ridge reform or does another trough drop into the center part of NA?  It has been my experience that La Nina cold comes in waves.  Usually the dam releases, a ridge builds back in, and we are fortunate, we get a second shot later in Jan or early Feb.  

I was going to note that if you watch carefully, there is almost a large cyclonic flow over all of NA.  The cold crosses the pole from Siberia which sees NA, is forced against the Rockies where it creates a huge cold air mass, warmth builds over the south, and the cold release SE once there is enough of it.  So you get pulses of cold which head SE.  A lot of those fronts wash out right as they hit E TN.  The cold if it can get something to move it quickly, is often well below normal.  You subtract those 2-3 weeks in 84-85, nobody talks about that winter.   That cycling flow, if it stays in place, would keep pulses of cold in the pattern for as long as that "feature" is in place.

[Holston_River_Rambler]

35 minutes ago, Carvers Gap said:

 What do you all see?

I think I can see the circulation you're talking about in the post just above mine. I think it is possible that helps reinforce some ridging in the NAO area. Lots of concern with the Pac across the weather forums and rightly so, but that's a sneaky pattern you've pointed out. It will be interesting to see how it evolves. 

[Holston_River_Rambler]

On a side note, the 12z Euro splits the SPV at 50 mb:

 

GFS ain't having much of it:

 

Still, it is under some stress at that level. 

 

The Euro even tries hard for a split at 10mb, but doesn't quite get there. 

The ever popular 3D vortex rendering gets some hits and wobbles at the lower levels, but looks stout overall:

 

 

 

 

[jaxjagman]

23 minutes ago, Carvers Gap said:

I suspect we fight that Aleutian ridge all winter...There is a reason people out West absolutely love La Nina winters.  Weak La Nina winters here(southern Apps) can be very cold at times(maybe even as a general rule), but not always.  People on the EC don't like La Nina winters.  West of the Apps it can work.  We don't need super cool weather in early January to have a chance.  Just need seasonal.  Right now if forced...I would way the trough lifts out around the 10th.  However, what happens after that is really open for debate.  Does the Pac ridge reform or does another trough drop into the center part of NA?  It has been my experience that La Nina cold comes in waves.  Usually the dam releases, a ridge builds back in, and we are fortunate, we get a second shot later in Jan or early Feb.  

I was going to note that if you watch carefully, there is almost a large cyclonic flow over all of NA.  The cold crosses the pole from Siberia which sees NA, is forced against the Rockies where it creates a huge cold air mass, warmth builds over the south, and the cold release SE once there is enough of it.  So you get pulses of cold which head SE.  A lot of those fronts wash out right as they hit E TN.  The cold if it can get something to move it quickly, is often well below normal.  You subtract those 2-3 weeks in 84-85, nobody talks about that winter.   That cycling flow, if it stays in place, would keep pulses of cold in the pattern for as long as that "feature" is in place.

Yes that Aleutian High is resiilient

[jaxjagman]

16 minutes ago, Holston_River_Rambler said:

I think I can see the circulation you're talking about in the post just above mine. I think it is possible that helps reinforce some ridging in the NAO area. Lots of concern with the Pac across the weather forums and rightly so, but that's a sneaky pattern you've pointed out. It will be interesting to see how it evolves. 

John made a good point a couple days ago this don't seem like a typical NINA.Believe that Aleutian high has been stronger than past Ninas causing some area out west for the heights to fall when they should actually rise