January 2021 Medium/Longterm Pattern Discussion.

[Carvers Gap]

Thanks, Holston.  This is a 30 day 500mb map of the Euro Weeklies which runs from Jan 13th to February 12th.  IF it is right, those anomalies might be stronger than that.  Cold air would move south from Alaska into the Mountain West(front range) and then move eastward.  My guess would be that Alaska is being fueled by cold from easter Siberia as evidenced by the 850 temps growing colder as the month goes on.  There are some really good weeks buried in that 30 day map below.  The blue arrow is obviously the path of cold air on the model.  The red is either cold fronts dragging into the GOM and tapping the Gulf or systems moving along the Gulf phasing with strong cold fronts.  Confluence would be over the East.  As long as we can avoid the trough tucking into the West and holding(need a little help in the west with even the slightest ridge), and that keeps coming eastward.  Pretty much the entire run from just after the 10th is this pattern.  I would be happy with just three weeks of that!  Huge grain of salt for all newcomers and tread lightly with LR maps.  The great thing is that we are seeing this pattern evolution on the GFS(18z has it) and all global ensembles at 12z.  Trough tucks into the SE, slight ridge pops out West, the pattern below commences.

[Daniel Boone]

5 minutes ago, Carvers Gap said:

Thanks, Holston.  This is a 30 day 500mb map of the Euro Weeklies which runs from Jan 13th to February 12th.  IF it is right, those anomalies might be stronger than that.  Cold air would move south from Alaska into the Mountain West(front range) and then move eastward.  My guess would be that Alaska is being fueled by cold from easter Siberia as evidenced by the 850 temps growing colder as the month goes on.  There are some really good weeks buried in that 30 day map below.  The blue arrow is obviously the path of cold air on the model.  The red is either cold fronts dragging into the GOM and tapping the Gulf or systems moving along the Gulf phasing with strong cold fronts.  Confluence would be over the East.  As long as we can avoid the trough tucking into the West and holding(need a little help in the west with even the slightest ridge), and that keeps coming eastward.  Pretty much the entire run from just after the 10th is this pattern.  I would be happy with just three weeks of that!  Huge grain of salt for all newcomers and tread lightly with LR maps.  The great thing is that we are seeing this pattern evolution on the GFS(18z has it) and all global ensembles at 12z.  Trough tucks into the SE, slight ridge pops out West, the pattern below commences.

 Looks good for Miller b/a hybrids. Ala 95-96 . Clippers too I suppose, particularly when Ridging pops in the West.

[Carvers Gap]

18 minutes ago, Daniel Boone said:

 Looks good for Miller b/a hybrids. Ala 95-96 . Clippers too I suppose, particularly when Ridging pops in the West.

There are some nice weeks like BullCity posted.  The thing I find encouraging is that the actual beginning of the pattern is on ensembles.  Seems like the past few winters have featured Weeklies patterns which stayed 2-3 weeks out and never got closer.  If I was looking for a problem, the only concern I would have is that some good looks in November dumped into the West after first being depicted for the East.  The Weeklies seem to split the difference between the November and December pattern and also fits SSW climatology in terms of blocking as you and Holston have mentioned (Jeff as well).    I don't like the MJO setup right now, but the SSW and -NAO could counterbalance that.  Encouraging run for sure!  

[Carvers Gap]

If one looks at the last week of the 18z GEFS, it has remarkable agreement with the Euro Weeklies.  

[Carvers Gap]

Good trends on today's GEFS extended as well.  Similar look aa the Weeklies.  Really hoping that modeling is feeling the disruption of the PV.  

[Holston_River_Rambler]

So I had my little attempt at analogues a couple of days ago, but Masiello did his own overnight:

 

I chose to use the 15th panel is his series of tweets because that's where the analogues are looped. Def. worth a full read through as his research above is much more thorough and, well, he is Masiello. He didn't pay as much attention to ENSO state as compared to me (I only chose La Ninas and he focused more on antecedent conditions involving a Ural/Barents High and an Aleutian Low). 

I think his conclusions were fairly similar to mine:

"Finally, here is the -5 to +35 day composite around the 3 SSW events of surface temperature anomalies. Southern Canada/CONUS in the composite do not significantly cool down until 20-30 days after SSW central date in these years."

I was looking more for blocking at 500 mb and found that it usually happened 10 - 20 days after the SSWE and that would seem to correlate to his conclusion, since the blocking happening at H5 would probably precede the cold dropping down by a bit. 

Now I don't think I have anything on Masiello, but I am happy that I somehow came to a similar conclusion, whether by coincidence or not. His thread was also a good lesson for me in how to look for analogues and use them. 

[Holston_River_Rambler]

Not sure if this is accurate or not, but wow:

 

[Carvers Gap]

Two very distinct MJO camps right now.  First one is the EMON which came out yesterday(Euro LR).  That is a BIG break in continuity for it. 

 

This one is the NCEP GEFSBC from this morning.  Pretty steady.

Sorry for the different sized photos.  Thought I had them resized similarly.  Anyway, those two solutions would create basically two, entirely different patterns over North America.  That is a massive break from continuity by the EMON.

 

[tnweathernut]

Not sure if this is accurate or not, but wow:
 

Been checking around and from all accounts appears accurate.


.

[Carvers Gap]

1 minute ago, tnweathernut said:

Been checking around and from all accounts appears accurate.


.

What are the surface reports under that in terms of temps?

[BNAwx]

10 minutes ago, Carvers Gap said:

What are the surface reports under that in terms of temps?

 

[Carvers Gap]

I should add that breaks in continuity are not bad.  Sometimes a model will break from the pack and be right, and sometimes it will be just be an outlier which doesn't verify.  Right now, the EMON MJO is an outlier.  However, how many times we have seen the Euro be an outlier only to win that battle?  Once the SSW (will it split?) is felt, I have seen modeling flip on a dime.  That can be good(Euro Weeklies yesterday, GEFS extended last night, 0z CFSv2 overnight) or bad (6z CFSv2 which is running now).   Wouldn't panic with one CFSv2 run.  Bounces around often during the same four runs of a single day.  The real thing to watch is the BN heights that slide through the SW and into the East beginning around the 10th.  If this goes the way of the Weeklies last night(and 0z EPS), that piece of energy should slide under the eastern ridge, form a trough in the East, pop a slight ridge around Southern California.  The 6z CFSv2 does show how this could go wrong.  Basically, the area of BN heights simply can't break through the eastern ridge, and the trough forms out West.  There is precedent for troughs being forecast in the East only to end-up out West - happened twice during November already.   I lean Euro right now.  The only pause I have is that the GEFS/GFS has done pretty well with previous strat splits.  However, it is January and the Euro is tough to beat once shoulder season is over.  Pretty exciting times to be following the weather.  Sure, there is possible dud option sitting on the table(that option is always there) and there is the potential for a really good winter pattern which is probably more likely than the dud.   What will be exciting is some of the wild swings possible now on modeling.  The close we get to this SSW, the more modeling will feel its influence.   Sure seems like some things are breaking in our favor.  However, we might not be completely certain of that until say Jan 3rd or 4th.  

[tnweathernut]

10 minutes ago, Carvers Gap said:

What are the surface reports under that in terms of temps?

Coldest temperature I can find not directly under is in Hodrogo, Mongolia.  They are 37 below (F) at 9:00 PM 

[Carvers Gap]

13 minutes ago, tnweathernut said:

Coldest temperature I can find not directly under is in Hodrogo, Mongolia.  They are 37 below (F) at 9:00 PM 

Did some digging as well.  This is from the Euro overnight.  Sorry for the small thumbnail.  Around hour 6, looks like eastern Russian is -52.9C which is about -63F.  That is craziness.  Looks like one, giant high pressure complex over Eastern Asia.   

 

[Carvers Gap]

That forecasted temp at hour 6 is 108 degrees colder than my forecast high of 45 today.  

[iluvsnow]

I find the daily world highs and lows at eldoradoweather.com. Here are the world's lowest daily temps.....not surprisingly....all in Siberia....

Minimum Temperature Last 24h - 12/29/2020 at 14:00 UTC

No.	Location	Station ID	Amount
1	Ojmjakon (Russia)	24688	-71.5°F
2	Delyankir (Russia)	24691	-68.3°F
3	Agayakan (Russia)	24684	-67.0°F
4	Yurty (Russia)	24588	-66.1°F
5	Susuman (Russia)	24790	-65.4°F
6	Nera (Russia)	24585	-65.2°F
7	Teplyj Klyuch (Russia)	24771	-61.8°F
8	Taskan-In-Magadan (Russia)	25700	-61.1°F
9	Tugoncani (Russia)	23589	-60.3°F
10	Ohotsky Perevoz (Russia)	24871	-58.0°F
11	Ust-Bakhapcha (Russia)	25707	-57.8°F
12	Verhoyanskij Perevoz (Russia)	24668	-57.8°F
13	Krest-Hal'dzhaj (Russia)	24763	-57.5°F
14	Ust'-Charky (Russia)	24371	-55.5°F
15	Curapca (Russia)	24768	-55.3°F
Script courtesy of  Michael Holden of Relay Weather. Data courtesy of Ogimet

 

[Holston_River_Rambler]

Y'all may have seen Webb tweeting about the Aleutian low too, I think this is the one that is spawned by that high's descent. Wonder how low that LP will verify? The EPS mean is 928 and I think the overnight OP was 923.

The 6z Euro best estimate is around 1070mb for the 1090+ HP:

 

And it has continued to adjust lower with the Aleutians low:

0z:

6z:

This is world record breaking stuff, up stream of us, and will continue to mess with the models until it resolves. 

[1234snow]

Y'all may have seen Webb tweeting about the Aleutian low too, I think this is the one that is spawned by that high's descent. Wonder how low that LP will verify? The EPS mean is 928 and I think the overnight OP was 923.
The 6z Euro best estimate is around 1070mb for the 1090+ HP:

 
And it has continued to adjust lower with the Aleutians low:
0z:

6z:

This is world record breaking stuff, up stream of us, and will continue to mess with the models until it resolves. 

I think the lowest pressure for that area is 924mb. Not sure about world record for non-tropical.

[jaxjagman]

Believe the strongest to date was in 2012?Don't quote me, i could be wrong.Believe it was on Halloween afterwards LeConte got 3 feet of snow

[nrgjeff]

I'm starting to like the Martin Luther King Day period for a colder pattern. Well I'm wishing. Can't say I like it as a forecast yet.

As Anthony notes North America has to hurry up and wait on the Strato warming and -AO. Right now Western Europe and China are cold due to blocking in the North Atlantic and also northeast of Scandinavia. Central Asia ridging helped promote that record surface high in Mongolia (Hoth, lol).

Read a paper about the effects of SSW. Old news is that it can cause cold in eastern North America, Western Europe, and eastern Asia (one, two or three of the areas). However the North America failures are not new. Actually we have little correlation with the time of max Strato warming or -AO. Western Europe has the most correlation with blocking cold. East Asia is second, and lower. North America is barely significant at all. This is AO not NAO.

Same study shows Alaska block has the higher correlation for North America. Not a surprise! We've been talking about that here. Though even I was a little intrigued just how poorly AO and even SSW correlate for North America - just not a big tool. The required Alaska ridge can happen 30 days following the North Pole true -AO. There is your North America lag.

So North America lag might not be truly accurate. We need to wait for the AK ridge, whether by retrograde, Pacific forcing, or some other method.

[AMZ8990]

17 minutes ago, nrgjeff said:

I'm starting to like the Martin Luther King Day period for a colder pattern. Well I'm wishing. Can't say I like it as a forecast yet.

As Anthony notes North America has to hurry up and wait on the Strato warming and -AO. Right now Western Europe and China are cold due to blocking in the North Atlantic and also northeast of Scandinavia. Central Asia ridging helped promote that record surface high in Mongolia (Hoth, lol).

Read a paper about the effects of SSW. Old news is that it can cause cold in eastern North America, Western Europe, and eastern Asia (one, two or three of the areas). However the North America failures are not new. Actually we have little correlation with the time of max Strato warming or -AO. Western Europe has the most correlation with blocking cold. East Asia is second, and lower. North America is barely significant at all. This is AO not NAO.

Same study shows Alaska block has the higher correlation for North America. Not a surprise! We've been talking about that here. Though even I was a little intrigued just how poorly AO and even SSW correlate for North America - just not a big tool. The required Alaska ridge can happen 30 days following the North Pole true -AO. There is your North America lag.

So North America lag might not be truly accurate. We need to wait for the AK ridge, whether by retrograde, Pacific forcing, or some other method.

All I heard was,  “we need to wait for”

lol.  Jk jk

Great stuff Jeff

[Met1985]

1 hour ago, nrgjeff said:

I'm starting to like the Martin Luther King Day period for a colder pattern. Well I'm wishing. Can't say I like it as a forecast yet.

As Anthony notes North America has to hurry up and wait on the Strato warming and -AO. Right now Western Europe and China are cold due to blocking in the North Atlantic and also northeast of Scandinavia. Central Asia ridging helped promote that record surface high in Mongolia (Hoth, lol).

Read a paper about the effects of SSW. Old news is that it can cause cold in eastern North America, Western Europe, and eastern Asia (one, two or three of the areas). However the North America failures are not new. Actually we have little correlation with the time of max Strato warming or -AO. Western Europe has the most correlation with blocking cold. East Asia is second, and lower. North America is barely significant at all. This is AO not NAO.

Same study shows Alaska block has the higher correlation for North America. Not a surprise! We've been talking about that here. Though even I was a little intrigued just how poorly AO and even SSW correlate for North America - just not a big tool. The required Alaska ridge can happen 30 days following the North Pole true -AO. There is your North America lag.

So North America lag might not be truly accurate. We need to wait for the AK ridge, whether by retrograde, Pacific forcing, or some other method.

Great stuff Jeff and I can remember in winters past were an SSW did not correlate to cold on this side of the globe. Im very skeptical of anything significant again on this side...

[John1122]

The blocking by day 8-10 on the Euro is just crazy. The EPS just says "hey Miller A, meet this cold" in the 11-15 day range. Now we just need to reel it in and we should have business picking up.

[PowellVolz]

Believe the strongest to date was in 2012?Don't quote me, i could be wrong.Believe it was on Halloween afterwards LeConte got 3 feet of snow

Wasn’t that from Sandy?


.

[Holston_River_Rambler]

I guess I should have been more specific. I don't mean to say that extratropical cyclone will be the world record, but just that that anticyclone/ cyclone combo is up in that rarified territory. 

Speaking of rarified... (the blocking John was talking about)

 

 

 

 

[Carvers Gap]

15 minutes ago, Holston_River_Rambler said:

I guess I should have been more specific. I don't mean to say that extratropical cyclone will be the world record, but just that that anticyclone/ cyclone combo is up in that rarified territory. 

Speaking of rarified... (the blocking John was talking about)

 

 

 

 

If correct, that is an awesome winter pattern.

[Carvers Gap]

1 hour ago, John1122 said:

The blocking by day 8-10 on the Euro is just crazy. The EPS just says "hey Miller A, meet this cold" in the 11-15 day range. Now we just need to reel it in and we should have business picking up.

Great look.  

[jaxjagman]

1 hour ago, PowellVolz said:

Wasn’t that from Sandy?


.

Probably right

[jaxjagman]

1 hour ago, PowellVolz said:

Wasn’t that from Sandy?


.

Wasnt sure i was right,believe it was this

https://en.wikipedia.org/wiki/November_2014_Bering_Sea_cyclone#North_America

[John1122]

The strat warming is actually underway now. Whether we benefit or not remains to be seen. By by and large we eventually see more snow than normal in the 60 days that follow.