December 2023 Mid/Long Term Pattern Discussion: Let it Snow!

[Knoxtron]

Just to tag along on Holston's post... really hoping to atleast get a good dusting on the Plateau. We are north of Chatt at 2100 Feet MSL so maybe a little hope 

 

 

GFS Snow Totals (this weekend)

 

Euro

 

 

[Daniel Boone]

3 hours ago, PowellVolz said:

Maybe I don’t pay attention enough but I can’t remember a trough just completely collapsing on the backside like this. I can anyone explain why this happened?


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Fast flow coming into PNW looks  like the problem; just shoving things along. 

[Carvers Gap]

If that PNA pops like it is on some modeling, the potential for very cold air masses to plunge southward is plausible.

[Daniel Boone]

MJO seems to want to redevelop in IO as it starts to come out into wpac. Is there a huge underwater Volcano in the IO or something !?! I mean.. geeze. . 

[John1122]

Looks like the short range models are getting more optimistic about the back side snow potential on Sunday. The 18z NAM has some decent snow showers and the 12z RGEM looked like it was doing well too. Waiting to see the 18z. 

 

18z NAM

 

[Carvers Gap]

Modeling is all over the place right now.  Source regions are a problem right now....I repeat, source regions are a problem.   It appears highly unlikely that the cold snap between Christmas and New Years is going to materialize.  Let's get that out of the way right now.  The western Atlantic ridge has holding power, and until it is gone...no chance of cold getting into the East.  Personally, I don't know that the MJO is playing a huge roll right now.  The IO is a problem if it is firing in the wrong place for sure - I haven't looked.  I think the 500mb pattern is still on track to switch, and looks REALLY good...but cold air will be hugely lacking until early January - that is a BIG change during the past 48 hours.  Now, that doesn't mean it won't snow.  We are getting to the time of the year where marginal set-ups can work(John just posted about that for reference).  All of that said, LR modeling has an ebb and flow to it re: temps, and things could change quickly.  I have a sneaking suspicion that the strat is getting hammered, and that could be taking a wrecking ball to LR modeling.  Remember this, when you see a big WAR(western Atlantic ridge), it is often a precursor to a very sharp cold snap 2-3 weeks later.  The Euro Weeklies are picking up on a storm tracking across the South during Christmas Eve...but for now we will call it a rainer.

So, to sum it up, the 500 pattern is right on track w/ one exception - a big western Atlantic ridge.  That said, BN heights under that ridge(where we live in the SE) exist.  Storm tracks to out south are starting to show up which is encouraging.  Most LR modeling is completely blind to cold snaps past 3 weeks...so any cold intrusion at all is going to have to be watched with this active STJ.  

The Alaskan low as it retrogrades into the Aleutians will possibly be like a dam break as it "should" release cold into North America during the first week of January.  Honestly, if it kicks the can about ten more days into mid-Jan, my winter forecast for January could hit - LOL, so I am good either way.  

Nino rains appear on tap, just need some cold...stay tuned. 

 

[Itryatgolf70]

9 minutes ago, Carvers Gap said:

Modeling is all over the place right now.  Source regions are a problem right now....I repeat, source regions are a problem.   It appears highly unlikely that the cold snap between Christmas and New Years is going to materialize.  Let's get that out of the way right now.  The western Atlantic ridge has holding power, and until it is gone...no chance of cold getting into the East.  Personally, I don't know that the MJO is playing a huge roll right now.  The IO is a problem if it is firing in the wrong place for sure - I haven't looked.  I think the 500mb pattern is still on track to switch, and looks REALLY good...but cold air will be hugely lacking until early January - that is a BIG change during the past 48 hours.  Now, that doesn't mean it won't snow.  We are getting to the time of the year where marginal set-ups can work(John just posted about that for reference).  All of that said, LR modeling has an ebb and flow to it re: temps, and things could change quickly.  I have a sneaking suspicion that the strat is getting hammered.  Remember this, when you see a big WAR(western Atlantic ridge), it is often a precursor to a very sharp cold snap 2-3 weeks later.  The Euro Weeklies are picking up on a storm tracking across the South during Christmas Eve...but for now we will call it a rainer.

So, to sum it up, the 500 pattern is right on track w/ one exception - a bug western Atlantic ridge.  That said, BN heights under that ridge(where we live in the SE) exist.  Storm tracks to out south are starting to show up which is encouraging.  Most LR modeling is completely blind to cold snaps past 3 weeks...so any cold intrusion at all is going to have to be watched with this active STJ.  

The Alaskan low as it retrogrades into the Aleutians will possible be like a dam break as it "should" release cold into North America during the first week of January.  Honestly, if it kicks the can about ten more days into mid-Jan, my winter forecast for January could hit - LOL, so I am good either way.  

Nino rains appear on tap, just need some cold...stay tuned. 

 

Kicking the can or chasing unicorns aren't fun lol. El Niños are usually back loaded. Hopefully patience is a virtue for us

[Carvers Gap]

I should also note that the Euro Weeklies have us at a net below normal for temps over the next 46 days, and that includes withstanding a major warm-up just prior to Christmas.  Precip for middle and western areas of the forum is shown to be well below normal.  Eastern areas are right on the border of seasonal and below.  So, I don't see a torch(other than right before Christmas)....just a lot marginal temp stuff.  Traditionally, we need a deep, cold air mass for snow...so marginal air masses make it trick.  This weekend is a great example.

[Carvers Gap]

3 minutes ago, Itryatgolf70 said:

Kicking the can or chasing unicorns aren't fun lol. El Niños are usually back loaded. Hopefully patience is a virtue for us

No kicking the can at 500.  I want to emphasize that at this time.  It honestly looks locked in.  If any cold whatsoever enters the pattern, it is heading SE.  So, the deliver mechanism is there...bu the coolant in the fridge is running on low.  Temps are just not as cold.  The low over Alaska is stronger along with the WAR.  That combo locks up cold.  LR modeling missed the WAR.  But the WAR could be a blessing in disguise if it does what I think it is going to do.  Definitely patience is always warranted during Nino winters.    Honestly, just looks like a typical Nino pattern in terms of cold.  As one of the posters noted in the MA forum, Canada is often not super cold during Nino winters.

[Holston_River_Rambler]

We're not all jumping on the snowman19 and bluewave wagon? 

[Itryatgolf70]

16 minutes ago, Holston_River_Rambler said:

We're not all jumping on the snowman19 and bluewave wagon? 

Bluewave is smart, but snowman19 don't like cold and repeats what other people say

[Itryatgolf70]

18 minutes ago, Carvers Gap said:

No kicking the can at 500.  I want to emphasize that at this time.  It honestly looks locked in.  If any cold whatsoever enters the pattern, it is heading SE.  So, the deliver mechanism is there...bu the coolant in the fridge is running on low.  Temps are just not as cold.  The low over Alaska is stronger along with the WAR.  That combo locks up cold.  LR modeling missed the WAR.  But the WAR could be a blessing in disguise if it does what I think it is going to do.  Definitely patience is always warranted during Nino winters.    Honestly, just looks like a typical Nino pattern in terms of cold.  As one of the posters noted in the MA forum, Canada is often not super cold during Nino winters.

The Alaska low is the main issue imo, which is tied to +epo

[Carvers Gap]

33 minutes ago, Holston_River_Rambler said:

We're not all jumping on the snowman19 and bluewave wagon? 

Who are those guys?

[Carvers Gap]

15 minutes ago, Itryatgolf70 said:

The Alaska low is the main issue imo, which is tied to +epo

Yes, it should be getting out of the way...sliding into the Aleutians.  The PNA is gonna pop...just a matter of when.  I think modeling was too quick.  Though certainly the Weeklies today are strong with the PNA than yesterday.

[Holston_River_Rambler]

Just now, Carvers Gap said:

Who are those guys?

I've just been spending a lot of time (probably moire than is healthy) in the main forum El Nino discussion thread watching the folks in there to see where they think things are going to fall out. I think it started out as a ENSO discussion but has kind of e- or de-volved (depending on your perspective) into a tropical forcing/ pattern progression thread. as I see it there are roughly two sides:

The bluewave/ snowman19 group who think that, to paraphrase Eric Webb from a month or so ago, that a hostile Pac jet, amped up by some sort of death standing wave in MJO phases 4/5/6, will pop an Aleutian so far east it will flood the CONUS with Pac puke. 
The 40/70 Benchmark/ brooklyn99/ griteater group who think a warm December is par for the course, but this will not be like 2015/16 winter (an analogue some of the other group seem to like). They think, like the ensembles/ monthlies/ seasonals are showing, that the Pac will be less hostile and assume a canonical Nino look, like many others have said elsewhere, as we move into early Jan. 

 

The above discussion is getting a tad testy sometimes (what can I say, its the internet, I like to watch). While the above summaries may be somewhat over simplified from what the above people are arguing, there seem to be a "we torch more often than not" group and a "decent Nino coming" group. 

I was just prompted to post the earlier comment since I know Daniel Boone has been somewhat active in that thread as an endorser (at least to my mind) of the 40/70 benchmark/ griteater/ brooklyn99 group and it seemed like he might be leaning more Bluewavey with the comment about the IO and the MJO.

Dan, didn't mean anything bad by it, just poking the bear a little so to speak. 

All this is probably a little bantery, but I have found the above discussion a useful supplement from a seasonal perspective. Who among us isn't a little gun shy after all the recent La Ninas, neutrals, and a weak Nino though?  It seems like everything is coming to a head with the current MJO wave. Does it spend more time that forecast in the 4/5/6 phases? Or does it continue strongly into the west Pac to and past the dateline? Does something totally unexpected happen? Can I type a little longer until the 18z GFS is finished running? Probably not. 

Right now I am with the 40/70, brooklyn99, griteater, and dare I say Carver's Gap group and think this is definitely a different beast from 15/16, but I guess we'll see how it goes. 

[Itryatgolf70]

27 minutes ago, Holston_River_Rambler said:

I've just been spending a lot of time (probably moire than is healthy) in the main forum El Nino discussion thread watching the folks in there to see where they think things are going to fall out. I think it started out as a ENSO discussion but has kind of e- or de-volved (depending on your perspective) into a tropical forcing/ pattern progression thread. as I see it there are roughly two sides:

The bluewave/ snowman19 group who think that, to paraphrase Eric Webb from a month or so ago, that a hostile Pac jet, amped up by some sort of death standing wave in MJO phases 4/5/6, will pop an Aleutian so far east it will flood the CONUS with Pac puke. 
The 40/70 Benchmark/ brooklyn99/ griteater group who think a warm December is par for the course, but this will not be like 2015/16 winter (an analogue some of the other group seem to like). They think, like the ensembles/ monthlies/ seasonals are showing, that the Pac will be less hostile and assume a canonical Nino look, like many others have said elsewhere, as we move into early Jan. 

 

The above discussion is getting a tad testy sometimes (what can I say, its the internet, I like to watch). While the above summaries may be somewhat over simplified from what the above people are arguing, there seem to be a "we torch more often than not" group and a "decent Nino coming" group. 

I was just prompted to post the earlier comment since I know Daniel Boone has been somewhat active in that thread as an endorser (at least to my mind) of the 40/70 benchmark/ griteater/ brooklyn99 group and it seemed like he might be leaning more Bluewavey with the comment about the IO and the MJO.

Dan, didn't mean anything bad by it, just poking the bear a little so to speak. 

All this is probably a little bantery, but I have found the above discussion a useful supplement from a seasonal perspective. Who among us isn't a little gun shy after all the recent La Ninas, neutrals, and a weak Nino though?  It seems like everything is coming to a head with the current MJO wave. Does it spend more time that forecast in the 4/5/6 phases? Or does it continue strongly into the west Pac to and past the dateline? Does something totally unexpected happen? Can I type a little longer until the 18z GFS is finished running? Probably not. 

Right now I am with the 40/70, brooklyn99, griteater, and dare I say Carver's Gap group and think this is definitely a different beast from 15/16, but I guess we'll see how it goes. 

If it stays in the warm phases, it won't be much different than 15-16 imo. Most want it to get into 8-3, but that's the difficult part figuring out when it could happen. I hear the olr charts are more accurate in determining where the mjo is currently so I guess most people should read those charts instead of the RMM charts for more confidence 

[Daniel Boone]

14 minutes ago, Holston_River_Rambler said:

I've just been spending a lot of time (probably moire than is healthy) in the main forum El Nino discussion thread watching the folks in there to see where they think things are going to fall out. I think it started out as a ENSO discussion but has kind of e- or de-volved (depending on your perspective) into a tropical forcing/ pattern progression thread. as I see it there are roughly two sides:

The bluewave/ snowman19 group who think that, to paraphrase Eric Webb from a month or so ago, that a hostile Pac jet, amped up by some sort of death standing wave in MJO phases 4/5/6, will pop an Aleutian so far east it will flood the CONUS with Pac puke. 
The 40/70 Benchmark/ brooklyn99/ griteater group who think a warm December is par for the course, but this will not be like 2015/16 winter (an analogue some of the other group seem to like). They think, like the ensembles/ monthlies/ seasonals are showing, that the Pac will be less hostile and assume a canonical Nino look, like many others have said elsewhere, as we move into early Jan. 

 

The above discussion is getting a tad testy sometimes (what can I say, its the internet, I like to watch). While the above summaries may be somewhat over simplified from what the above people are arguing, there seem to be a "we torch more often than not" group and a "decent Nino coming" group. 

I was just prompted to post the earlier comment since I know Daniel Boone has been somewhat active in that thread as an endorser (at least to my mind) of the 40/70 benchmark/ griteater/ brooklyn99 group and it seemed like he might be leaning more Bluewavey with the comment about the IO and the MJO.

Dan, didn't mean anything bad by it, just poking the bear a little so to speak. 

All this is probably a little bantery, but I have found the above discussion a useful supplement from a seasonal perspective. Who among us isn't a little gun shy after all the recent La Ninas, neutrals, and a weak Nino though?  It seems like everything is coming to a head with the current MJO wave. Does it spend more time that forecast in the 4/5/6 phases? Or does it continue strongly into the west Pac to and past the dateline? Does something totally unexpected happen? Can I type a little longer until the 18z GFS is finished running? Probably not. 

Right now I am with the 40/70, brooklyn99, griteater, and dare I say Carver's Gap group and think this is definitely a different beast from 15/16, but I guess we'll see how it goes. 

Lol. Yeah, you summed it up perfect over there. I'm actually leaning a decent Winter snowwise overall, even December ftm as I've alluded to before.. Have just began to see some truth to the Bluewave argument regarding the MJO and the problem the 500 MB has had characteristically as compared to Years with similar Enso as the WPAC/ IO are so warm it clearly shows a response . Domino effect west to East. Hopefully, the sure strength of the Nino and HLB can off set the forcing from that broad very warm SST Area. The fear in my mind would be an Alaskan Vortex in place of Aleutian LP. If HLB strong enough , that would keep that on back in the Aleutians. That's what I'm rooting for as a counter along with mainly Central based Nino forcing . ( in laymen's terms).

[Carvers Gap]

2 hours ago, Itryatgolf70 said:

If it stays in the warm phases, it won't be much different than 15-16 imo. Most want it to get into 8-3, but that's the difficult part figuring out when it could happen. I hear the olr charts are more accurate in determining where the mjo is currently so I guess most people should read those charts instead of the RMM charts for more confidence 

I think we see a really good winter.  I just wanted to get everyone ready for great 500 maps which have poor source regions.  Some of our best winters started late.   Some of our worst winters took the same path (warm start) and never started.  LOL.  
 

The storm track itself is what has me encouraged.  The WAR gives me pause as almost all LR modeling missed it completely.  So, we have a fox(WAR) in the henhouse, and I proceed carefully when I see it.  But generally, that creates an SSW.   The strat just gets hammered.  Almost all extended ensembles remove the WAR by the middle of the last week of December.  I think we have to wait on the really cold air until January.  That fits climatology - decent 500 pattern but marginal cold.

I do think our patience will be rewarded.

[Daniel Boone]

33 minutes ago, Carvers Gap said:

I think we see a really good winter.  I just wanted to get everyone ready for great 500 maps which have poor source regions.  Some of our best winters started late.   Some of our worst winters took the same path (warm start) and never started.  LOL.  
 

The storm track itself is what has me encouraged.  The WAR gives me pause as almost all LR modeling missed it completely.  So, we have a fox(WAR) in the henhouse, and I proceed carefully when I see it.  But generally, that creates an SSW.   The strat just gets hammered.  Almost all extended ensembles remove the WAR by the middle of the last week of December.  I think we have to wait on the really cold air until January.  That fits climatology - decent 500 pattern but marginal cold.

I do think our patience will be rewarded.

Good post and points man. Storm track is encouraging and the war actually appears to maybe be a bit east of the last bad years with it. SST's are somewhat different along the coast than previous times. The STJ probably will help keep it further East also wouldn't you think ? 

  

.

[Carvers Gap]

23 minutes ago, Daniel Boone said:

Good post and points man. Storm track is encouraging and the war actually appears to maybe be a bit east of the last bad years with it. SST's are somewhat different along the coast than previous times. The STJ probably will help keep it further East also wouldn't you think ? 

  

.

The best thing about LR guidance is almost a complete absence of the SER.

[Daniel Boone]

1 minute ago, Carvers Gap said:

The best thing about LR guidance is almost a complete absence of the SER.

Yeah man !!! Big change from recent years.

[John1122]

The 18z NAM stepped to and beyond the RGEM on the back side of the weekend system. Especially for the Eastern Rim/Western Plateau area. The 0z backed off. 

[Itryatgolf70]

36 minutes ago, Carvers Gap said:

The best thing about LR guidance is almost a complete absence of the SER.

Carver, go read tomer burg's tweets on Twitter from a few hours ago. Very interesting stuff. Eric Webb made good post also. Monster highs overseas!! Wished we could tap some of that

[fountainguy97]

Wow the NAM quite literally takes me from 67 to mid 20s in 12 hrs. Lightning to heavy snow.  Sunday may be an absurd weather day if that takes place.

[Carvers Gap]

8 hours ago, Itryatgolf70 said:

Carver, go read tomer burg's tweets on Twitter from a few hours ago. Very interesting stuff. Eric Webb made good post also. Monster highs overseas!! Wished we could tap some of that

Yeah, Europe has been hammered.  I was not a huge fan of Webber taunting people in the Mid-Atlantic, and then completely flipped to their viewpoint a few weeks later.  He used to be much more metric driven, and maybe this season not as much....but he is a good met.  He has bounced around a bunch this fall.  I probably should do more weather Twitter(I used to), but I don't think I have looked at a weather Tweet since last year(other than what is shared here).  I probably should do more Twitter(nothing against the company), but wx Twitter just got to where it had too much hype and they were grabbing information from forums like this. 

Amy Butler is a good read for all things strat-warming. 

[Carvers Gap]

6 hours ago, fountainguy97 said:

Wow the NAM quite literally takes me from 67 to mid 20s in 12 hrs. Lightning to heavy snow.  Sunday may be an absurd weather day if that takes place.

The 6z GFS is a wild run end to end.  That run is an exemplar of what a Nino winter could look like.   Yes, mountain communities could have a wild ride if the 6z GFS is remotely correct.   Mountain communities like Mountain City, Roan Mountain, Unicoi/Erwin, and the Burg.

[Carvers Gap]

Now, if you want to see a REALLY wild feature.  Look at the last 36 hours of the GFS run in Canada.  I was trying to find how they were getting +55F anomalies (anomalies!) in northwest Canada.  It is a monster Chinook, and I mean monster.  The low in the Aleutians has to be absolutely spinning super high winds into the Rockies there.  That floods Canada with incredibly warm air, but it likely also will factor in popping the PNA right after that.  Just a very strong and volatile weather pattern on the 6z GFS across much of NA.  And I mentioned the SE coastal lows that form....crazy fun run.

I for sure will double down on yesterday's post and reiterate that truly cold air is probably at least a month out.  However, storms and rumors of storms will precede any cold intrusion...and we might have a chance with just seasonal climatology and storm track.

[Carvers Gap]

And with a flurry of posts, I have to head to the school car line...the 6z NAM and RGEM look interesting for the higher elevations of NE TN/Plateau.  I can never tell if those models really see the valleys or just put snow IMBY to smooth things out. But that might need its own thread if we are seeing that at 0z. 

[Holston_River_Rambler]

Guess I'll go ahead and pull the trigger:

 

 

 

 

 

 

 

 

 

 

…THUNDER IN THE MOUNTAINS WATCH IN EFFECT FROM 12Z SUNDAY THROUGH

0Z MONDAY...

 

* WHAT…Thunder in the Mountains and plateaus is possible 

* WHERE...Plateaus and mountains east TN, southwest VA, western NC, and eastern KY

* WHEN...From Sunday morning through Sunday evening

* IMPACTS…thunder bolts and lightning, very very frightening 

 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Thunder in the Mountains WATCH is issued when the risk of THUNDER AND LIGHTNING is significantly increased during meteorological winter, but the weather weenie issuing the watch is nervesome about a warning. It is intended to provide additional lead time for those who who may wish watch the SREF plumes for anafrontal shortwave snow or a potential pattern change. 

[Knoxtron]

I can move this post if a dedicated thread is started 

 

Total snow thru Monday afternoon (12-12)

 

GFS

 

EURO

 

Canadian