Winter Speculation 17/18 -December Thread

[Carvers Gap]

I had a little time to burn at lunch today.  Tagging onto Jax's post and my earlier posts...here are some graphics that one can look at in the LR.  Call it the mid-winter halftime speech.

Here is the QBO. It is negative at 30hPa and likely headed that way at 50hPa.  Strong signs of blocking when in negative territory.  It is there now.  Those times have correlated to cold and snowy periods over the forum area.

Here are my "go-to" MJO indices.  The higher the amplitude, the greater the impact.  The -QBO might alter some of those as Jeff noted some recent research that was just shared.  I am a fan of the BOMM(Australia), Euro, and GEFS.  I also like the JMA.  Note the low amplitude that many are now trending to in phase 4.  Also, note that many are headed into the Circle of Death(COD) which means the MJO would be at such low amplitude that it would have low impact on the weather here in eastern NA.  We want it in phases 8,1,2,3.  You all know when we start talking about the MJO that the pattern is in a lull.  LOL.

  

   

Here are today's CPC ensembles...Note the rise in the PNA for early February and the potential drop in the AO.  The NAO remains positive.  "Looks" like a predominantly decent +PNA timeframe ahead.  I know John is a big fan of the Pacific needing to be right.  I tend to agree...though I do like the increasingly rare -NAO.

  

Here is the EPO forecast.  Note that it is headed positive which is a signal for our thaw.  Also note that it takes a peak at negative in early February which aligns with the idea that February will turn cold possible transitioning there during the second week.

 

Weeklies will roll tonight.  I am sure there will be some commentary on that.  Maybe Jeff will give us a preview once it rolls.

 

[John1122]

If the Pacific is good, we're good. If it isn't we aren't. I've given up on a negative NAO being more than a unicorn. The SE has been getting pounded with winter storms this year without it being negative. We got rocked in 2013-14, 2014-15 and 2015-16 while it was predominantly positive.  The Pacific, especially the EPO, seems to overwhelm the pattern for good or for ill.

I know the MJO can hurt at times, but it too doesn't really pack the influence of the Northern Pacific. Last year I think it went through 7-8-1 at high amplitude and the N Pac was unfavorable so we roasted. I think it made the trip in 2014-15 with a favorable N. Pac and we snow/cold bonanza'd.

[Carvers Gap]

46 minutes ago, John1122 said:

If the Pacific is good, we're good. If it isn't we aren't. I've given up on a negative NAO being more than a unicorn. The SE has been getting pounded with winter storms this year without it being negative. We got rocked in 2013-14, 2014-15 and 2015-16 while it was predominantly positive.  The Pacific, especially the EPO, seems to overwhelm the pattern for good or for ill.

I know the MJO can hurt at times, but it too doesn't really pack the influence of the Northern Pacific. Last year I think it went through 7-8-1 at high amplitude and the N Pac was unfavorable so we roasted. I think it made the trip in 2014-15 with a favorable N. Pac and we snow/cold bonanza'd.

Indeed, we cycled through a great MJO...but zero cold in Canada last year.  This year it is there to be tapped.  But yeah, I hear you.

Hey, did you catch the 12z Euro?....sure looks like it is ready to pop a -EPO/+PNA ridge combo after that last trough swings through at d10.  It might even be there already.  Good sign IMO if that look holds.  I think the Bering Straits ridge will eventually slide or morph into an EPAC ridge.  

[John1122]

The EURO control builds the EPO ridge over Alaska but slides the trough into the west. That pumps a ridge here beyond day 10. It's repeatedly shown that look but it never comes to fruition this winter.

[Carvers Gap]

1 hour ago, John1122 said:

The EURO control builds the EPO ridge over Alaska but slides the trough into the west. That pumps a ridge here beyond day 10. It's repeatedly shown that look but it never comes to fruition this winter.

But we do know one thing when it shows that look...that trough is going correct East....and it gets cold.  Nice look on the EPS late in its run.   Was transitioning to an EPO/PNA ridge out West w/ cold pushing down the front of the Rockies into the Plains.  Looks an awful lot like Dec 24 on Feb 2.

[Carvers Gap]

Weeklies Update:  Really, no changes to the last Weeklies update that I had....so, just scroll back and find that.  The 2m temps and 500 pattern were less extreme, but I just chalk that up to variations based on the model run that they extrapolate from.  If the Weeklies had been derived from the 12z run...it would have been stone cold.  Either way, the control run showed repetitive shots of cold rotating down a steep EPO/PNA ridge.  The control really seems to want to switch the pattern around Feb 8th.  The mean is fairly close to that time frame.  The mean also does the dance where it gets energy hung in the southwest....remember the run-up to Christmas.  We were all frustrated that the models would not correct eastward.  Same deal.  If the correction eastward takes place, instead of a stretched out trough from New Mexico to Greenland, then the run would have been very cold.  But as Jeff says, we know the model bias and can correct that for ourselves vs having a model that is just random.  So, good run of the Weeklies.  I will say that the mean for snow was cut in half, likely due to the past weekend's storm not being in the mix.  Besides, the Weeklies snow means are just eye candy...they really have little substance.  Now, the control did show almost two feet for NE TN.  So, there is that.   Aaaand.....once the pattern returns to cold, it maintains and strengthens the run into the first week of March where the run ends.  So, looks like chances for snow at least into the beginning of March for the entire forum area.  Jeff, feel free to put your two cents in....

[John1122]

If we have cold from February 8th til March 8th we should have 2 or 3 shots at something. I believe we all had a major storm or two in that time frame 3 of the last 4 years. 

[Carvers Gap]

1 hour ago, John1122 said:

If we have cold from February 8th til March 8th we should have 2 or 3 shots at something. I believe we all had a major storm or two in that time frame 3 of the last 4 years. 

At least.  You bet.  That is my take as well.  Really good shot just based on generalities at this range. 

[weathertree4u]

8 hours ago, Carvers Gap said:

At least.  You bet.  That is my take as well.  Really good shot just based on generalities at this range. 

yea, feel pretty good about our chances. Looks like the southern stream is going to be really active and with cold lurking not too far away, I like our chances! Some years, we are still waiting this time of year for something to track and we have already done that for sure!

[Coach B]

1 hour ago, *Flash* said:

It is interesting to note 9 of Nashville's top 15 snows occurred in February/March...

Only one of the top 10 was in January and three of the top ten were not only in March, but the second half of March!

Add to note: I have noticed in the last 25 years that all directions from Nashville seem to regularly record higher amounts. I wonder if this is due to incorrect measurements from observers or simply Nashvile's very low elevation down in a bowl and heat island effect compared to the surrounding areas. Or is it a combination??

Another note: the late 70s were considered some of the best for snow and cold and are not on the list at all!

[jaxjagman]

50 minutes ago, *Flash* said:

It is interesting to note 9 of Nashville's top 15 snows occurred in February/March...

1. 22.8 inches (February 2-3, 1886)
2. 17.0 inches (March 17, 1892)
3. 15.0 inches (February 20-21, 1929)
4. 10.2 inches (Dec. 31, 1963-Jan. 1, 1964)
5. 9.2 inches (November 23-24, 1950)
6. 9.7 inches (February 25, 1894)
7. 8.8 inches (February 11, 1910)
8. 8.7 inches (March 19, 1996)
9. 8.5 inches (January 29, 1905)
10. 8.2 inches (March 20, 1968)
11. 8.1 inches (January 7, 1988)
12. 8.0 inches (February 14, 1902)
13. 8.0 inches (January 22, 2016) 
14. 7.5 inches (January 22, 1966)
15. 7.5 inches (March 4, 1917)
16. 7.4 inches (December 22-23, 1963)
17. 7.4 inches (February 8, 1960)
18. 7.3 inches (January 5, 1960)
19. 7.2 inches (November 2, 1966)
20. 7.0 inches (January 16, 2003)
21. 7.0 inches (January 16, 1948)
22. 6.7 inches (February 1, 1985)
23. 6.5 inches (January 11, 1918)
24. 6.2 inches (January 23, 1963)
25. 6.2 inches (January 19, 1936)
26. 6.1 inches (January 21, 1888)
27. 6.0 inches (December 18, 1916)
28. 6.0 inches (February 11, 1895)

Upon further review, if we could bring back the late 19th century, that'd be awesome...

I was thinking the same thing looking at that chart

[John1122]

Heck, the 1960s are on there 8 times. #4 and #18 happened a week apart. 

[nrgjeff]

Late January cold appears to have faded back to run of the mill cold fronts behind mainly rain system(s). OK by me to take a breather.

February should offer 2 cold weeks. Tough to say if 2 in a row, or a cold-warm-cold deal. Weeklies both line up well with new Alaska ridging and a Great Plains blue norther. SER shown has not held up any other time this winter. February La Nina climo supports the SER slightly more, but I'm going with the trend. Surface temps should be colder than shown, dissecting the 500 mb progs. Technical term for low level cold air undercutting SER is a General Sherman job. Not really.

What about snow? February climo is the least bad for snow. Peer reviewed research goes anywhere from January to March; however, we're going with February. One inland low east of the Apps but without a quick coastal transfer would fill most of the gaps. Also those January Deep South sliders are for us in Feb. I am probably too optimistic. Playing on house chips after getting clippered pretty well in Illinois. However we do have cold weather forecast in the best climo month.

MJO will be a big player, but I believe the models are confused. Right now deep convection is noted over all of the Indian Ocean, stretching all the way to the eastern tip of Indonesia. Won't stop raining in the Philippines. Convection spans several regions on the MJO chart, so the number is not as useful this situation. I expect a quicker weaker move through the warm phases. Cold phases should return by Feb.

[Carvers Gap]

16 minutes ago, nrgjeff said:

Late January cold appears to have faded back to run of the mill cold fronts behind mainly rain system(s). OK by me to take a breather.

February should offer 2 cold weeks. Tough to say if 2 in a row, or a cold-warm-cold deal. Weeklies both line up well with new Alaska ridging and a Great Plains blue norther. SER shown has not held up any other time this winter. February La Nina climo supports the SER slightly more, but I'm going with the trend. Surface temps should be colder than shown, dissecting the 500 mb progs. Technical term for low level cold air undercutting SER is a General Sherman job. Not really.

What about snow? February climo is the least bad for snow. Peer reviewed research goes anywhere from January to March; however, we're going with February. One inland low east of the Apps but without a quick coastal transfer would fill most of the gaps. Also those January Deep South sliders are for us in Feb. I am probably too optimistic. Playing on house chips after getting clippered pretty well in Illinois. However we do have cold weather forecast in the best climo month.

MJO will be a big player, but I believe the models are confused. Right now deep convection is noted over all of the Indian Ocean, stretching all the way to the eastern tip of Indonesia. Won't stop raining in the Philippines. Convection spans several regions on the MJO chart, so the number is not as useful this situation. I expect a quicker weaker move through the warm phases. Cold phases should return by Feb.

Great write-up and thanks!

[weathertree4u]

3 hours ago, *Flash* said:

It is interesting to note 9 of Nashville's top 15 snows occurred in February/March...

1. 22.8 inches (February 2-3, 1886)
2. 17.0 inches (March 17, 1892)
3. 15.0 inches (February 20-21, 1929)
4. 10.2 inches (Dec. 31, 1963-Jan. 1, 1964)
5. 9.2 inches (November 23-24, 1950)
6. 9.7 inches (February 25, 1894)
7. 8.8 inches (February 11, 1910)
8. 8.7 inches (March 19, 1996)
9. 8.5 inches (January 29, 1905)
10. 8.2 inches (March 20, 1968)
11. 8.1 inches (January 7, 1988)
12. 8.0 inches (February 14, 1902)
13. 8.0 inches (January 22, 2016) 
14. 7.5 inches (January 22, 1966)
15. 7.5 inches (March 4, 1917)
16. 7.4 inches (December 22-23, 1963)
17. 7.4 inches (February 8, 1960)
18. 7.3 inches (January 5, 1960)
19. 7.2 inches (November 2, 1966)
20. 7.0 inches (January 16, 2003)
21. 7.0 inches (January 16, 1948)
22. 6.7 inches (February 1, 1985)
23. 6.5 inches (January 11, 1918)
24. 6.2 inches (January 23, 1963)
25. 6.2 inches (January 19, 1936)
26. 6.1 inches (January 21, 1888)
27. 6.0 inches (December 18, 1916)
28. 6.0 inches (February 11, 1895)

Upon further review, if we could bring back the late 19th century, that'd be awesome...

It is interesting i think to note that the lat 1800's were also low solar time periods 

[jaxjagman]

Euro MJO shows it going into almost 2 sigma of where it was Dec 16th.Euro is showing a big Omega into Kamchatka into Russia into the long range with East Asia getting really active and cold in Asia.Potential looms for an active period the end of wk 1 into 2 of Feb in the Valley.CFS is lagging with the MJO, still has it into the IO today and keeps it strong until it reaches phase 7 mid month,more  likely why it shows a more stronger SER and much warmer look in Feb

 

[jaxjagman]

No signs of any SST right now,you need this to uptick alot more.maybe Feb.Was looking at the March Madness thread just now,here's the RRWT into early March what it's showing.Most of all the seasonals look BN in March as well as the RRWT shows into Mid March.Nina still hanging out.

 

Edit:Most of the seasonals shows us AN in March,worded that wrong

[jaxjagman]

Just to clarify the post above,not all the seasonals agree with each other in March.

[jaxjagman]

RRWT is showing the coldest air anomalies in Northern Hemisphere is going to be on our side into wk 2-3 of Feb.Question would be,will it be right and what comes with it,trough axis,etc.etc.

[John1122]

What an odd GFS run. Perfect Miller A track, but of course no cold to be found anywhere so it's raining into Canada. Then the low appears to transfer from just off the Florida panhandle to Southern Indiana, where it becomes a cutter. Never saw a low transfer from the coast to inland.

[jaxjagman]

MJO is still looking strong on the Euro ,around 2 sigma and getting ready to get into phase 8.RRWT still looks brutal cold into wk2 of Feb.IF it gets that cold in the deep south should be records broken.

SOI today and the past few days show some of the best Nina like conditions we've seen yet,consistent anyways.

15 Jan 2018	1013.52	1006.35	12.06	-3.05	3.39
16 Jan 2018	1012.84	1004.60	17.11	-1.82	3.48
17 Jan 2018	1013.11	1003.65	22.85	-0.74	3.63
18 Jan 2018	1013.63	1005.20	18.00	0.07	3.73
19 Jan 2018	1013.25	1005.55	14.56	0.61	3.85
20 Jan 2018	1012.99	1004.90	16.40	1.24	4.03

 

If the control is anywhere right,it's showing some great signs today in its long range in Canada.Remind you though, it's at the end of the run so use caution,posted the 500mb Height Amomaly

[weathertree4u]

53 minutes ago, jaxjagman said:

MJO is still looking strong on the Euro ,around 2 sigma and getting ready to get into phase 8.RRWT still looks brutal cold into wk2 of Feb.IF it gets that cold in the deep south should be records broken.

SOI today and the past few days show some of the best Nina like conditions we've seen yet,consistent anyways.

15 Jan 2018	1013.52	1006.35	12.06	-3.05	3.39
16 Jan 2018	1012.84	1004.60	17.11	-1.82	3.48
17 Jan 2018	1013.11	1003.65	22.85	-0.74	3.63
18 Jan 2018	1013.63	1005.20	18.00	0.07	3.73
19 Jan 2018	1013.25	1005.55	14.56	0.61	3.85
20 Jan 2018	1012.99	1004.90	16.40	1.24	4.03

 

If the control is anywhere right,it's showing some great signs today in its long range in Canada.Remind you though, it's at the end of the run so use caution,posted the 500mb Height Amomaly

That is great but if we have no moisture then we are back where we were in December/January

[Carvers Gap]

17 minutes ago, weathertree4u said:

That is great but if we have no moisture then we are back where we were in December/January

Ninas can be dry wx patterns...but I am counting on the changing wave lengths of February to do the dirty work.  I say bring the cold. We have had a decent amount of snow in the forum area this winter, just not IMBY or in the eastern Valley.  If we are right back to Dec/Jan w February wavelengths...I think we will have several happy forum members.  That pattern had Memphis and western forum areas written all over it.  The upcoming pattern(if it verifies...don't want to count my chickens before they hatch) would be similar to what Jeff described IMO.  Those Deep South systems would shift to our forum areas and the coastal systems shift inland.  The SER will be a battle....all usual caveats apply.  But bring me the Dec/Jan pattern....we will score w/ that nine out of ten times.  So, in my mind I see sliders, cutters, and inland runners for this area.  Sounds like I am a pitcher.

[Carvers Gap]

5 hours ago, John1122 said:

What an odd GFS run. Perfect Miller A track, but of course no cold to be found anywhere so it's raining into Canada. Then the low appears to transfer from just off the Florida panhandle to Southern Indiana, where it becomes a cutter. Never saw a low transfer from the coast to inland.

That is a very potent system that is showing up.   You bring up some great points. Odd energy transfer.  The energy coming from lower latitudes (much lower than normal) seems to hold and mesh with an incoming system.  The big coastal blizzard did that.  I am used to seeing systems grab energy from the central and northern GOM, but it seems like some of this energy is originating in the southern Caribbean (party hyperbole, partly true....Yucatan and Cuba).  Will be interesting to watch.

[jaxjagman]

The next chance of snow in the Valley should be around the end of wk 1 of Feb.All the models show this in Asia,just timing differences.We see a system in Korea and it builds a ridge off of Japan.This should correlate to a system in the Valley and a  Mid Atlantic ridge in time.Guess the question will be is there a SER that could hold back the heights.Not really sure what will happen right now,could be snow,could be cold rain or could be severe,GEFS picks up on this

[jaxjagman]

Euro 0z lost the storm by the looks,go figure..lol..Use the ensembles right now,GEFS and GEPS still shows a system the end of week 1 INTO 2.Not sure right now if it's winter or rain

 

Edit:Might not be anything now,Euro lost it and the GEFS AND GEPS wants to cut it off around the Bajas,model mayhem,expect another swing tomorrow with this pattern

[jaxjagman]

Not sure what tidbits did with the models,but i liked it the other way.But anyways,volatile pattern upcoming

[Carvers Gap]

This is day 15 on the 0z EPS.  Very similar to 12z and moving forward in time now.  Also, it is important to note that when a trough has appeared in the East this winter...it has usually been under modeled in strength.  On this run, cold does not penetrate into the South as much as late Dec/Jan.  IMO, that is probably a good thing.  Definitely will deal w a SER at times as others have mentioned.   Looks to me like the storm pattern would shift from the Gulf Coast to over the forum area(when compared to the earlier cold shot and fits w/ Jeff's ideas).   Below is cold look...but unlikely a dry look.  That said, if this is under modeled...could be very cold and dry.  Again, I am still banking on a February pattern w/ wavelengths and frequency that will be different than that of mid-winter.  But I think the map below shows the transition back to cold as nearly complete.  EPO ridge in place.  Trough sneaking back east of HI.  Trough resuming over NE Asia.  The NA trough is likely hanging back a bit much as the control does the "over under" deal w/ the EPO ridge and SW trough.  So, likely some members are causing the NA trough axis to lean more positively than potential actuality...if it verifies a trough is swinging through at that time.  Plenty of cold in Canada is available.  

[Carvers Gap]

That is a Miller A at 174ish on the 12z GFS.  Panhandle to inland runner.  Temps are warm...but something to watch.  That time frame has been one that models are keying on for a system.  Will need that to be stronger so as to crash temps...a weak system will be cold rain.  But that looks almost like a pure Miller A money track.  Who knows if the GFS is right, but it has been close on several runs?  But something to watch.  At the very least, that track would hammer higher elevations and the foothills.  

[Carvers Gap]

12z CMC has the same system in the same spot...Miller A.