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Riccardo

Seasonal winter 2013/2014 forecast based on OPI index

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In this paper, although we are still in autumn, is proposed the seasonal winter 2013/2014 forecast, based on the new numeric model obtained from the recent research about the correspondence between october and winter (DJF – December, January and February) geopotential patterns, from which it is obtained the new index OPI (“October Pattern Index” – A new highly predictive index for the winter season)

 

http://www.americanwx.com/bb/index.php/topic/41379-october-pattern-index-predicting-winter-ao-from-october-with-90-accuracy/

 

Before proceding in this topic a premise in necessary. The Our knowledge about the climate of the North American continent is poor in comparison to those relating to the European continent. For this reason, the present analysis not will provide detailed anticipation like in european case.

First attention is for the value that OPI have reached at the end of last October: it stands on high value about +1.6. This value suggest a winter quarter average characterized by a very compact Polar Vortex  (average Artic Oscillation near +1 or above). In this situation (high AO) the westerliess, due to the cyclonic activity of the polar Vortex, are more intensive and frequently confined at northern geographic latitude. This “ring of strong wind”, that turn around the North Pole, tipically bound cold air masses in the polar region, determining a more stable regime of high pressure on the middle latitudes.

 

qe82.png

Fig. 1. This picture show typical geopotential anomaly on North America (at isobaric level of 500 hPa) detected at the end of winter season with Polar Vortex average strong (high AO with value equal +1 or greater).

 

 

The evidence of this is obtained from the analysis of the geopotential anomaly above the North Pole, which provide relevant indications about  the Polar Vortex “healt” on all its isobarica profile.

 

qjwt.png

 

Fig. 2. This picture show the geopotential height anomaly on the entire column of  Polar area.

 

Regard this, the particular dynamics that featured the first part of last October will trigger progressive stratospheric response from Novembre to December due to the progressive reinforcement of Stratospheric Pola Vortex.The effect is a primary forcing steer  of a compact and poor modulable Polar Votex (ESE Cold), like OPI have brilliantly shown.

 

vujx.png

 

Fig. 3. This picture shows the divergence of planetary wave and, for the conservation of angular momentum, the progressive  deepening of stratospheric Polar Vortex.

 

 

 

So far the attention has been paid at average trend of winter and have remarked how it result average featured of the weak planetary wave activity with resulting strong Polar Vortex. However during the cold season we could see at some brief phase in which there could be a greater planetary waves activities and therefore favorable to a more marked jet stream oscillation. In this case North America could be affected by very cold air masses. In this regard, how specified in our reseach, the OPI careful analysis and the October pattern from which it follows, is possible also infer enough detailed information about the salient features of the most important cold advection. For this scope in first below show the reanalysis hemispheric  map of the geopotential anomaly at isobaric level of 500 hPa for the last October month.

 

eomi.png

 

Fig. 4. This picture show the hemispheric geopotential anomaly (at isobaric level of 500 hPa) of October 2013 (2013 October Pattern).

 

 

From the careful analysis map, the primary October pattern characteristics are:

 

1)      central axis of the vortex (black line) moderately inclined, joining Labrador and eastern Siberia; the axis position and OPI value are output of “Telemappa Next Generation” software;

 

2)      very low elliptical component index of weake stationarity and intrusiveness of the planetary waves.

 

Also, in virtue of near correspondence between average October pattern and circulation model characterizing the focal cold event of the following winter (“key event” in which the planetary waves activity is more intense in the winter), from the above reanalysis map and in refer the montly axis (black line), is possible infer featured of the most relevant winter events. In our case you notice a Pacific wave (wave 1) translated, compared to the usual position, on the eastern sector of north Pacific (Alaska gulf) and the Atlantic wave (wave 2) in symmetrical position respect to the axis (black line) positioned on the eastern Atlantic (United Kingdom - Scandinavia).

This planetary waves configuration (wave 1 – 2) suggest a compact Polar Vortex condition and weake planetary waves intrusiveness (in particular for wave 2) also in the most strong activity pahses. On the other hand the high OPI value, as well as the large negative anomaly centered from noth Scandinavia and Kara sea, support the thesis of a favorable circulation schema in which the Altlantic wave (wase 2) isn’t intrusiveness on high northern latitudes however in AO neutral/positive context. About location of the Pacific wave (wave 1), it result centered into western eastern pacific sector (Alaska gulf).

This configuration should favor a strong advection of cold arctic air masses to the central-eastern areas of the American continent during the increased activity of the planetary wave. The following figure depicts in great lines the circulatory pattern described in reference only to the American continent:

 

7kss.png

Fig. 5. This picture shows  a type of pattern similar to that outlined. The anomalies refer to the portion of 500 hPa geopotential. From this denotes the anticyclone well centered over the Gulf of Alaska with the strong arctic current directed mainly on the central and eastern areas of the continent.

 

 

Finally, about general timing, October pattern analysis suggest that the best planetary wave activities (major winter events), should be appeared at the beginning of the winter season (from late November to begin December) and almost at the end of the winter season. In fact the careful analysis of the October pattern development suggests a premature start to the winter season strongly enough. After this phase the intensification of the Polar Vortex (weak planetary wave activities) should dominate the central part of the winter season favoring stable and mildness conditions. The planetary wave activity should resume only in the last part of Janary, weak at the beginning, with restoring of winter season typical conditions. This waves activity should reach best expression about at first half/central part of February, when they might occur the best cold advection, with greater involvement of the low latitudes.

Again we emphasize, as already expressed, the poor knowledge about North American climate.For this reason this forecast aims to provide general information about climatic events base on new predictive index OPI (index that today is best correlated with mean value of the  Arctic Oscillation computed on the months of December, January and February), and the discovering about a strong correspondence from the October geopotential pattern and following winter season pattern. Therefore more detailed information, that lie outside from our knowledge of American continent climate, we hope will be interpreted in the best way.

 

 

In order to follow our discussion about winter forecast, we invite you to click the following link:

 

http://www.centrometeotoscana.it/forum/index.php?topic=7473.0

 

 

 

Riccardo Valente, Alessandro Pizzuti, Filippo Casciani and Andrea Zamboni, member of the Center for Study on Climate and Teleconnections of "Centro Meteo Toscana"

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The November stratosphere continues to point to a strongly +AO winter. I have found a strong correlation between November east+central Asian stratosphere temperatures and the Dec-Jan AO (I would estimate R-squared of .8 or even .9 based on an ability to correctly predict the sign of the AO 9+ times out of 10). 

 

The stratosphere over eastern+central Asia has been frigid thus far. 

 

Thus the three best tools I know of to predict the winter AO (the OPI, SAI, and Nov. Asian stratopshere temps) all point to a strongly positive AO this winter.

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All signs point to another lousy winter unless one lives further north.

Can we re-run the teleconnections versus corresponding analogs in 2 weeks? At least before punting this winter.

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   are you actually making the   argument  that  +AO  in  early NOV  NEVER  changes  phases  in the Winter Months?

 REALLY? 

dont mean to sound harsh here  but  were  you   like  drunk when made this  obviously  absurd   assertion?

 

since  1950  the following   OCTOBERS  had  Moderate to strongly   POSITIVE  AO  values  yet  the  Winters  features  either   late Turn around  ( feb  / march)
in the AO into  Negative  Phase... 1954-55   1956-57    1961-62 


AND these   OCT  +AO  featured FULL turn around   of the AO into  negative in   DJF  1957-58 ( a great eastern us winter)  1958-59  1963-64  ( great eastern US winter)  
1964-65  1965-66( great winter)  1967-68  1969-70    1970-71   1978-79  (legendary)  1984 -85  1995-96  (legendary  winter)   and 2005-06  

 

 

The November stratosphere continues to point to a strongly +AO winter. I have found a strong correlation between November east+central Asian stratosphere temperatures and the Dec-Jan AO (I would estimate R-squared of .8 or even .9 based on an ability to correctly predict the sign of the AO 9+ times out of 10). 

 

The stratosphere over eastern+central Asia has been frigid thus far. 

 

Thus the three best tools I know of to predict the winter AO (the OPI, SAI, and Nov. Asian stratopshere temps) all point to a strongly positive AO this winter.

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THANKS  but its just this one topic. This OPI thing is     flawed  BIG time

 

 recall that   method  that  this guy   CHUCK   a met student   had  for  forecasting the   AO  and went for a  blow torch    for the winter  and  how is    could not possibly fail?

 

 

Welcome back, DT!

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Are these OPI   folks  actually making the   argument  that  +AO  in  OCT   NEVER  changes  phases  in the Winter Months?

 REALLY? 

dont mean to sound harsh here  but   this is crap 

 

since  1950  the following   OCTOBERS  had  Moderate to strongly   POSITIVE  AO  values  in OCOTBER yet  the  Winters  features  either   late Turn around  ( feb  / march) 
in the AO into  Negative  Phase... 1954-55   1956-57    1961-62 

AND   these   OCT  +AO  featured FULL turn around   of the AO into  negative in   DJF  
1957-58 ( a great eastern us winter)  
1958-59  1963-64  ( great eastern US winter)  
1964-65  
1965-66( great winter)  
1967-68  
1969-70    
1970-71  
1978-79  (legendary)  
1984 -85  
1995-96  (legendary  winter)  
and 2005-06  

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Are these OPI   folks  actually making the   argument  that  +AO  in  OCT   NEVER  changes  phases  in the Winter Months?

 REALLY? 

dont mean to sound harsh here  but   this is crap 

 

 

This is meant to predict the predominant phase of the AO, certainly does not preclude periods of AO-. For instance, 2011-2012 averaged a bit under +1 AO for the winter so it was a +AO winter but there was a notable period of a strongly negative AO mid winter that brough parts of Europe and Asia extreme cold, though the mega AK vortex/strongly positive EPO kept it mainly warm for much of the US.

And if you can predict the predominant AO phase for the winter, it can aid in predicting the average temperature because of the correlation between a +AO and overall warmth and -AO and overall cold in the eastern US. The SAI and OPI predicted a -AO last winter that verifed, and if not for the strongly positive EPO in December, the JFM period in which the AO can be predicted by these tools certainly averaged colder than normal in the eastern half of the US. I firmly believe that the OPI, SAI and currently frigid stratospheric temps over Siberia do entail a +AO winter, but the Pacific (EPO) will have a say on whether it's a near normal (slightly above average) or well above average winter.

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Are these OPI   folks  actually making the   argument  that  +AO  in  OCT   NEVER  changes  phases  in the Winter Months?

 

DT,

 Welcome back!!

 

 I don't think they are saying that a +AO in Oct. never changes phases in the subsequent winter. For Oct., they are looking at snow advance in Eurasia below 60N, not the phase of the AO (unless I'm missing something). So, I didn't think they were even considering the Oct. AO at all. Please correct me if I'm misunderstanding this.

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Are these OPI   folks  actually making the   argument  that  +AO  in  OCT   NEVER  changes  phases  in the Winter Months?

 REALLY? 

dont mean to sound harsh here  but   this is crap 

 

since  1950  the following   OCTOBERS  had  Moderate to strongly   POSITIVE  AO  values  in OCOTBER yet  the  Winters  features  either   late Turn around  ( feb  / march) 

in the AO into  Negative  Phase... 1954-55   1956-57    1961-62 

AND   these   OCT  +AO  featured FULL turn around   of the AO into  negative in   DJF  

1957-58 ( a great eastern us winter)  

1958-59  1963-64  ( great eastern US winter)  

1964-65  

1965-66( great winter)  

1967-68  

1969-70    

1970-71  

1978-79  (legendary)  

1984 -85  

1995-96  (legendary  winter)  

and 2005-06  

Hello DT.

I believe that you have understand very little about true signified of our research (not by chance you can not read the paper). But I believe that you have not read also this short forecast, because there is clearly written  that, average, the winter will be a AO++ winter (AVERAGE) and that there will be two  most important anti-zonal phases during all winter: the first at the beginning (and november- first part of december) and the second in febrary (expecially in the middle). Both these phases (features and time scheduling) have been understood through the october pattern analysis. 

However I don't want to persuade you beforehand, so we will "meet" at the and of winter and see if will be more exact our forecast than that of the "ufficial authority", which use others approachs end methods. 

 

Goodbye

 

Riccardo

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This is meant to predict the predominant phase of the AO, certainly does not preclude periods of AO-. For instance, 2011-2012 averaged a bit under +1 AO for the winter so it was a +AO winter but there was a notable period of a strongly negative AO mid winter that brough parts of Europe and Asia extreme cold, though the mega AK vortex/strongly positive EPO kept it mainly warm for much of the US. And if you can predict the predominant AO phase for the winter, it can aid in predicting the average temperature because of the correlation between a +AO and overall warmth and -AO and overall cold in the eastern US. The SAI and OPI predicted a -AO last winter that verifed, and if not for the strongly positive EPO in December, the JFM period in which the AO can be predicted by these tools certainly averaged colder than normal in the eastern half of the US. I firmly believe that the OPI, SAI and currently frigid stratospheric temps over Siberia do entail a +AO winter, but the Pacific (EPO) will have a say on whether it's a near normal (slightly above average) or well above average winter.

Stratospheric temps are not frigid over Siberia.

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Folks would really benefit from actually reading the posts by Riccardo and the links the in OP thread before trashing Riccardo's work.

 

 

This DT guy has apparently trashed this forum, Cohen, and the OPI.  He is pals with JB, Ryan Maue and so on.

 

Which also have a guy who claims his "proprietary" NAO forecast calls for the third most negative NAO winter. 

 

Unlike Cohen and the OPI he offers zero incite to his so called "methods."

 

If Riccardo's and Cohens work was showing a -AO.  This thread would have hundred of posts with folks patting each other on the back. 

 

I have seen dozens of posts all over the interwebs talking about a possible -AO winter.  Most of them know about the OPI and Cohen.

 

 

The thing is.  After 30-40 years of 83% and 91% and 97%(last 12 years) correlations.  How can anyone think this year the OPI and SAI will both break so bad they would be proven to be totally wrong?

 

Come on now.  Ain't Happening.

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He wants to post--let him post. The science will take care of itself. Many of us have known DT for years--it's be great to have him post again here. Acerbic? Questioning? Brutal language? Yeah--i wont argue. He's basically the Nietzsche of meteorologists. So lets just see what happens. And we can be a better forum by having him here. I think. Despite the controversy.

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Folks would really benefit from actually reading the posts by Riccardo and the links the in OP thread before trashing Riccardo's work.

 

 

This DT guy has apparently trashed this forum, Cohen, and the OPI.  He is pals with JB, Ryan Maue and so on.

 

Which also have a guy who claims his "proprietary" NAO forecast calls for the third most negative NAO winter. 

 

Unlike Cohen and the OPI he offers zero incite to his so called "methods."

 

If Riccardo's and Cohens work was showing a -AO.  This thread would have hundred of posts with folks patting each other on the back. 

 

I have seen dozens of posts all over the interwebs talking about a possible -AO winter.  Most of them know about the OPI and Cohen.

 

 

The thing is.  After 30-40 years of 83% and 91% and 97%(last 12 years) correlations.  How can anyone think this year the OPI and SAI will both break so bad they would be proven to be totally wrong?

 

Come on now.  Ain't Happening.

 

 I think DT thinks that the Cohen/Ricardo winter prediction of AO is based on the Oct. AO and DT is saying that's nonsense. DT said this in this thread:

 

 "Are these OPI folks  actually making the   argument  that  +AO  in  OCT   NEVER  changes  phases  in the Winter Months?'

 

 Actually, I'd think similarly to DT if that's what the theory said. However, we know that's not what is says. The winter AO prediction is based on the Oct. snow advance index, not the Oct. AO. So, I think DT is getting the wrong message due to his misinterpreting.

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Folks would really benefit from actually reading the posts by Riccardo and the links the in OP thread before trashing Riccardo's work.

 

 

This DT guy has apparently trashed this forum, Cohen, and the OPI.  He is pals with JB, Ryan Maue and so on.

 

Which also have a guy who claims his "proprietary" NAO forecast calls for the third most negative NAO winter. 

 

Unlike Cohen and the OPI he offers zero incite to his so called "methods."

 

If Riccardo's and Cohens work was showing a -AO.  This thread would have hundred of posts with folks patting each other on the back. 

 

I have seen dozens of posts all over the interwebs talking about a possible -AO winter.  Most of them know about the OPI and Cohen.

 

 

The thing is.  After 30-40 years of 83% and 91% and 97%(last 12 years) correlations.  How can anyone think this year the OPI and SAI will both break so bad they would be proven to be totally wrong?

 

Come on now.  Ain't Happening.

 

One lesson to be learned is that we never say never. If this is historically an 83 or 91 or 97% favorite, then what did the winters look like that defied the odds? Did we have a brutal winter when the index showed that it would be a positive AO? Please list the years that went against the grain. I think that there are a lot of folks interested in that data.

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One lesson to be learned is that we never say never. If this is historically an 83 or 91 or 97% favorite, then what did the winters look like that defied the odds? Did we have a brutal winter when the index showed that it would be a positive AO? Please list the years that went against the grain. I think that there are a lot of folks interested in that data.

 

 

Looks like years with massive ENSo changes had the weakest correlation.  Most years though the correlation is near perfect.

 

 

opi and ao.jpg

 

 

Given the current ENSO state.  We will probably see the OPI almost nail the prediction. 

 

Even if we took the top 5 years where it was off.  We would still only get down to a .75 to 1.0 AO+ unless we break the record on the OPI index and essentially destroy the correlation. 

 

 

I am not saying it wont be cold.  I am saying there wont be a neutral or negative AO.  It will be highly positive. 

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Hello DT.

I believe that you have understand very little about true signified of our research (not by chance you can not read the paper). But I believe that you have not read also this short forecast, because there is clearly written  that, average, the winter will be a AO++ winter (AVERAGE) and that there will be two  most important anti-zonal phases during all winter: the first at the beginning (and november- first part of december) and the second in febrary (expecially in the middle). Both these phases (features and time scheduling) have been understood through the october pattern analysis. 

However I don't want to persuade you beforehand, so we will "meet" at the and of winter and see if will be more exact our forecast than that of the "ufficial authority", which use others approachs end methods. 

 

Goodbye

 

Riccardo

Ricardo,

 

Do you have any idea as to when your paper will be available? The paper would probably clear up a lot of things.

 

Certainly from what you described, your approach looks promising and I wish you success with it. Anything that reduces uncertainty will be helpful.

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I believe what DT is referring to is the SAI and OPI's disregard for the rapid advance of snow cover during the last week of September as per his own winter outlook:

"The CONTRARY point of view on WHY the BIG OCT 2013 increase in Snow cover in Siberia doesn’t count

Their argument goes like this: If you Look at the SNOW Build up/ expansion from OCT 1 to NOV 1 in Siberia … the much above snowfall that fell in late SEPT undercuts the OCT snow cover build up. In other words the SEPT snow means that the OCT snow RATE OF CHANGE in building snow cover was NOT that impressive.

That argument is DELUSIONAL. The SAI is a Physical Process”

the rapid build up of Siberian snow cover in OCT which impacts the AO Phase in the Winter months. There is nothing special about OCT 1 vs say SEPT 25.

There is no possible reason WHY snow in late SEPT would mean a weaker SAI in OCT but IF the same snow in late Sept were to fall says 4 or 5 days later… it would enhance the SAI in October."

I know this controversy has been beat to a pulp here, but DT does have a very good point. Even if this winter turns out AO++, it good to see some mets argue against the norm and challenge what many here otherwise see as obvious.

DT, it's good to see you back. Keep posting.

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Actually that has all been addressed.

And secondly it's an indisputable fact that Cohen has an 83% correlation to the DJFM AO. And the OPI is 91% for DJF.

So I'm not sure what DTs problem is.

Is he saying the AO will be negative?

If he thinks the science is bad he should bring data to disprove the SAI and OPI.

If not what is the problem.

Lets do it this way. The OPI predicts a 1.6 DJF AO.

Everyone post there AO prediction for DJF. We can see how it goes in in March.

I will go with 1.3 for DJF.

And 0.9 for DJFM.

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Wow.

 

1.  He fully endorses whomever Al is and his NAO predictive index.  Whomever this Al is uses a "PROPRIETARY" method.  So DT has no idea how he comes up with it.  On twitter the guy wouldn't share it with other pro mets.  So again Mr. DT has one page dedicated to this in his presentation but completely goes after Cohens index.  But not Cohen just the METS who are delusional and think October is the end all be all.

 

 

 

DTsbullshit_zps0b6881b4.jpg

2.  This is a slide from the presentation where DT explains himself and the SAI.

 

 

DTsbullshit_zpscfd2c6b1.jpg

 

 

 

 

 

That is an interesting question, so I tested it by calculating the slope from 9/27 to 10/27 (31 days). Unfortunately, the change in the slope is insignificant. There's no way of getting around the fact that late September and early October had anomalously high snow cover.

 

Attached Images

SAI2.png

 

 

 

So what is his argument?  He went off about the October dates.  When we include September the slope still sucks.  And we get big +AO forecasts. 

 

There is no way to spin this. 

The correlations are 83% for the SAI for DJFM

91% for the OPI for DJF

97% for the OPI for DJF since 2000.

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Just a point of clarification. The OPI is not based on snow cover advance like the SAI is. It is based on the northern hemisphere 500 mb wave pattern during the full month of October. Now, it is likely that the same Oct wave pattern that produces negative OPI values is one that also leads to rapid snow advance, but that is not always the case per Riccardo's examples.

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So what is his argument? He went off about the October dates. When we include September the slope still sucks. And we get big +AO forecasts.

There is no way to spin this.

The correlations are 83% for the SAI for DJFM

91% for the OPI for DJF

97% for the OPI for DJF since 2000.

Well i think DT would like to see the rate run from say...sept 24 to oct 24, but i think many see the SAI as having a weakness in seasons where a tremendous snow cover is already present at when the index starts calculating. To me it seems some cherish something that supposedly is a breakthru in LR forecasting so much that a potential scenario that does seem to show a weakness in the way the slope could only really be flat is knee jerk blasphemy (if oct 1 already has near record snow coverage) but , yes this has been beaten like a dead horse, only thing is not everyone is on same page.

Anyhow , i realize this thread is for OPI and Riccardo's work and i so far am very impressed by his findings and forecast. It looks like he could nail the late Nov. / early Dec period in east /central areas.

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For what it is worth:

Year    DJFM AO    NegStdAnom SAI_Orig    NegStdAnom SAI_-3    NegStdAnom SAI_-5    NegStdAnom SAI-7    NegStdAnom SAI-9
2004    -0.26    0.49    -0.19    -0.53    -0.43    -0.55
2005    -1.01    0.33    0.55    0.50    0.40    0.28
2006    1.05    0.40    -0.38    -0.87    -1.35    -1.43
2007    0.79    1.14    1.25    1.36    1.20    0.92
2008    0.22    0.17    0.37    0.50    0.81    1.20
2009    -2.67    -1.87    -1.53    -1.16    -0.69    -0.50
2010    -0.33    0.29    -0.01    0.22    0.41    0.47
2011    0.75    0.12    1.34    1.42    1.37    1.16
2012    -1.64    -1.74    -1.61    -1.47    -1.49    -1.57
2013        0.73    0.30    0.18    -0.07    0.03
----    ----    ----    ----    ----    ----    ----
MAE (AO-SAI)        0.59    0.64    0.83    0.94    0.96


Wherein SAI-x, the x is the number of day earlier the 31 period of for calculation is started.  Standard is JD 304-374, and x=-9 is 265-295.  Data: ftp://sidads.colorado.edu/pub/DATASETS/NOAA/G02156/4km/

 

-- Jacob

post-9767-0-22484900-1384805224_thumb.pn

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Well i think DT would like to see the rate run from say...sept 24 to oct 24, but i think many see the SAI as having a weakness in seasons where a tremendous snow cover is already present at when the index starts calculating. To me it seems some cherish something that supposedly is a breakthru in LR forecasting so much that a potential scenario that does seem to show a weakness in the way the slope could only really be flat is knee jerk blasphemy (if oct 1 already has near record snow coverage) but , yes this has been beaten like a dead horse, only thing is not everyone is on same page.

Anyhow , i realize this thread is for OPI and Riccardo's work and i so far am very impressed by his findings and forecast. It looks like he could nail the late Nov. / early Dec period in east /central areas.

 

 

In agree with you.  I would be very happy if you told about the development of our winter forecast in this page (for OPI there is a specific page). In fact I would take advance  of this post in order to  understand something about the north America circulation. For example, I would understand by you the importance and the characteristics  of the likely next artic phase (that we have discreetly expected in our seasonal winter forecast).

Thank you very much.

 

Riccardo

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Lets do it this way. The OPI predicts a 1.6 DJF AO.

Everyone post there AO prediction for DJF. We can see how it goes in in March.

I will go with 1.3 for DJF.

And 0.9 for DJFM.

 

I'll go with +1.0 for DJF and +.5 for JFM.

 

I'll also say that I think the EPO is a significant factor some may be overlooking in forecasting a +AO blowtorch winter for much of the U.S. This fall has resembled a number of falls that were followed by major -EPO during the winter and some very cold temps at times in the U.S.: 1959, 1978, 1993, etc.

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I'll go with +1.0 for DJF and +.5 for JFM.

 

It looks like we agree March will be more negative?

 

I wouldn't mind a negative Feb-March.  All of us can for the most part get big snows in those times.

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