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Winter Outlook 2018-2019


40/70 Benchmark
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not to be contrarian buuut... 

I thought climo on warm ENSOs was for early cold/snow turn outs fading toward early springs... But, I don't know where Feb lands in that plan (exactly) ...it's a fence month.  Seasons lag...it's the only reason why Novie's aren't on whole snowier than they are, and why Febbies aren't bloomin.  the latter is getting more solar than the former.  

anyway, ...the warm ENSO isn't it kind of paltry? .

.. i also have a separate hypothesis related to it's scale/degree of anomaly being less meaningful in a GW where/when the surrounding medium is also warm(ing)... that skews the total thermal source/sink relationship and quite intuitively, a warm(cool) ENSO event in a warm(cool) earth should reflect differently...  

plus... again, i don't think enough homage is necessarily applied to the AO - not Ray's outlook per se...just in the general ambit of the efforts for seasonal 'casting. 

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1 hour ago, Typhoon Tip said:

not to be contrarian buuut... 

I thought climo on warm ENSOs was for early cold/snow turn outs fading toward early springs... But, I don't know where Feb lands in that plan (exactly) ...it's a fence month.  Seasons lag...it's the only reason why Novie's aren't on whole snowier than they are, and why Febbies aren't bloomin.  the latter is getting more solar than the former.  

Warm ENSO climo is for a back loaded winter.

anyway, ...the warm ENSO isn't it kind of paltry? .

Yes, which is why I think that we wilk have many miller Bs.

.. i also have a separate hypothesis related to it's scale/degree of anomaly being less meaningful in a GW where/when the surrounding medium is also warm(ing)... that skews the total thermal source/sink relationship and quite intuitively, a warm(cool) ENSO event in a warm(cool) earth should reflect differently...  

Warm ENSO events are still behaving in the same manner.

 

plus... again, i don't think enough homage is necessarily applied to the AO - not Ray's outlook per se...just in the general ambit of the efforts for seasonal 'casting. 

I think that the AO is addressed plenty...

 

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Just now, Typhoon Tip said:

yeah i routinely get that backward ...wrt to the direction there. 

but i'm not sure i know what you mean by 'warm ensos behaving in similar manner'  ... ?

What I mean is that ENSO related forcing has manfiested itself into the atmosphere as it always has climotalogically speaking.....dependent upon intensity and modoki value, etc..

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1 hour ago, 40/70 Benchmark said:

What I mean is that ENSO related forcing has manfiested itself into the atmosphere as it always has climotalogically speaking.....dependent upon intensity and modoki value, etc..

Mm... it was vetted/researched why the recent 'mega' nino did less comparative global impacts -

Winters since have also been odd relative to enso - 2015 ...etc

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49 minutes ago, Typhoon Tip said:

Mm... it was vetted/researched why the recent 'mega' nino did less comparative global impacts -

Winters since have also been odd relative to enso - 2015 ...etc

Global is one thing, but it looked pretty status quo to me stateside..weak el nino and uber el nino behaved as I expected....but annual precip in the Philippines...maybe.

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16 hours ago, 40/70 Benchmark said:

Global is one thing, but it looked pretty status quo to me stateside..weak el nino and uber el nino behaved as I expected....but annual precip in the Philippines...maybe.

Ah...personally? I wouldn't be so confident in picking the effect of ENSO apart that way...   

Whether the effect of Nina(Nina) may or may not be physically manifesting at a given location/season, only belies it's presence ... or supports it, either way. But when it doesn't, it doesn't mean it's not there.  It "sounds" like you're suggesting that? If so, ..no, it's effects are still ubiquitous. ..on going..  if only [more likely] being masked by whatever those other forces are hiding.  'Stateside' this and Philippines that ...I'd be careful with that. 

That very real and applicable concept is related to the AO part of this too.  There are times when the N. Hemispheric pancake events and emergent blocking episodes will subsume the ENSO signal (though probably less than entirely...) and whether it does so and how much probably depends on the relative strength of either in time.. blah blah.  

Also, and hypothetically:  El Nino is more than merely statistically shown to be a global phenomenon ... but, the majority of that history was in a relative quiescent/stable climate ... compared to the "hockey-sticking" we are observing world-over now.  The point was/is ... that statistical inference/correlations may be a bit tricky.   That's all...  It has to be... A warming world doesn't supply the gradient distribution the same way - gradient is the whole machinery, period.

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10 minutes ago, Typhoon Tip said:

Ah...personally? I wouldn't be so confident in picking the effect of ENSO apart that way...   

Whether the effect of Nina(Nina) may or may not be physically manifesting at a given location/season, only belies it's presence ... or supports it, either way. But when it doesn't, it doesn't mean it's not there.  It "sounds" like you're suggesting that? If so, ..no, it's effects are still ubiquitous. ..on going..  if only [more likely] being masked by whatever those other forces are hiding.  'Stateside' this and Philippines that ...I'd be careful with that. 

That very real and applicable concept is related to the AO part of this too.  There are times when the N. Hemispheric pancake events and emergent blocking episodes will subsume the ENSO signal (though probably less than entirely...) and whether it does so and how much probably depends on the relative strength of either in time.. blah blah.  

Also, and hypothetically:  El Nino is more than merely statistically shown to be a global phenomenon ... but, the majority of that history was in a relative quiescent/stable climate ... compared to the "hockey-sticking" we are observing world-over now.  The point was/is ... that statistical inference/correlations may be a bit tricky.   That's all...  It has to be... A warming world doesn't supply the gradient distribution the same way - gradient is the whole machinery, period.

So what are you saying, its a coincidence that we are still getting severe winters during weak el nino events, and they are not manifesting themselves as they have historically ?

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11 minutes ago, 40/70 Benchmark said:

So what are you saying, its a coincidence that we are still getting severe winters during weak el nino events, and they are not still manifesting themselves as they have historically ?

Well :D not in absolute terms like "...are not"  ...

I just want to consider the possibility of the latter ... to open some worth-while speculation and conjecture. I don't believe I've made any 'declarations' per se - if I did I miss spoke.

Hot vs cold ...undulations occur...system finds a neutralized outcome.  

Hot vs Hot ... no undulations occur ...because system has no physical reason to neutralize. 

I just strongly believe it is worth sciencing whether warm ENSO events in a GW spike might try to approach the the hot vs hot model ...not necessarily be there.  Throwing in the AO mucks it up further.    

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1 minute ago, 40/70 Benchmark said:

Oh, yea its possible......but for now, show me a weak modoki ENSO event and I'll show you an above average seasonal snowfall forecast for SNE. lol

well...yeah ...in your defense, I wasn't even considering the recent spatial science/delineation of ENSO anomalies - as in, 'where' the warmth is located out there. 

But it shouldn't matter - if there is a muting effect that is secondary to El Nino's presence ...because the El Nino is concurrent against a warm backdrop ...yadda yadda... It still would be influenced the same way.  

The problem here is that in a 'climate flux' ... you don't have Modoki this... and Nino 1+2 that actually IN that same historical framework... why?  because it hasn't happened yet.  

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1 minute ago, Typhoon Tip said:

well...yeah ...in your defense, I wasn't even considering the recent spatial science/delineation of ENSO anomalies - as in, 'where' the warmth is located out there. 

But it shouldn't matter - if there is a muting effect that is secondary to El Nino's presence ...because the El Nino is concurrent against a warm backdrop ...yadda yadda... It still would be influenced the same way.  

The problem here is that in a 'climate flux' ... you don't have Modoki this... and Nino 1+2 that actually IN that same historical framework... why?  because it hasn't happened yet.  

I have read that modoki events may be more common place in a warmer world....why, not sure-

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7 minutes ago, 40/70 Benchmark said:

I have read that modoki events may be more common place in a warmer world....why, not sure-

It's fascinating ...  

Perhaps time will expose that it's like a heat 'catch basin' that occurs during otherwise neutral times.   

It's an illusion of an El Nino event in that sense [if so] because it's only warmer than normal against 1950 but not necessarily in a neutral ENSO in 2020 ...  hmm

The other thing, NASA ...NOAA...  tea leafs in china... whatever, they may already "normalize" the anomaly for the hockey-sticking...  (I'm calling it hockey-stickinig, just means rapid rise at the end of the multi-decadal curve). That would make the "actual" Earth-relative anomaly (as in present tenths) more accurate.  But, the atmospheric component of that is a quagmire -

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4 minutes ago, Typhoon Tip said:

It's fascinating ...  

Perhaps time will expose that it's like a heat 'catch basin' that occurs during otherwise neutral times.   

It's an illusion of an El Nino event in that sense [if so] because it's only warmer than normal against 1950 but not necessarily in a neutral ENSO in 2020 ...  hmm

The other thing, NASA ...NOAA...  tea leafs in china... whatever, they may already "normalize" the anomaly for the hockey-sticking...  (I'm calling it hockey-stickinig, just means rapid rise at the end of the multi-decadal curve). That would make the "actual" Earth-relative anomaly (as in present tenths) more accurate.  But, the atmospheric component of that is a quagmire -

Don't they use 1980-2010 period to derive ENSO anomaly?

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50 minutes ago, 40/70 Benchmark said:

Don't they use 1980-2010 period to derive ENSO anomaly?

Not entirely sure... CPC provides a lot of on-line 101 level essay and explanation text for their various Q&A and methods ...etc...  They sort of tip their hat to 'not really normalizing for the hockey-sticking' (so to speak), however:

 

What is the relationship between El Ni�o/La Ni�a and global warming?

The jury is still out on this. Are we likely to see more El Ni�o's because of global warming? Will they be more intense? These are questions facing the science community today. Research will help us separate the natural climate variability from any trends due to man's activities. If we cannot sort out what the natural variability does, then we cannot identify the "fingerprint" of global warming. We also need to look at the link between decadal changes in natural variability and global warming. At this time we cannot preclude the possibility of links but it is too early to say there is a definite link.

c/o: http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensofaq.shtml#RELATIONSHIP

 

Their exact data ranges may be buried in those links somewhere .. but, climate intervals are broken into different multi-decadal lengths for different uses. Edit, might be useful to note that even since 1980...the lion's share of mass occurred in the latter half of that nearly 40 year span

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  • 4 weeks later...

Quick update...no changes. Ironically enough, it is the southeastern states of Virginia and North Carolina that are receiving the major snows since the PNA did join forces with high latitude blocking, but this is irrelevant in the grand scheme of things. The blocking did indeed materialize, and is on borrowed time, as advertised. Everything seems to be going as planned..too bad the early Dec event didn't work out for most of the east coast.

Bad luck.

This may sound silly, but I'm ambivalent about December struggling....if you look back at all of our most prolific weak modoki seasons, they all struggled in December snowfall wise, with the exception of one....December 1977.

December 2014, 2004, and 1968 were all fairly meager snowfall months. December 1976 was a prolific month during a weak el nino, but it was not a modoki. It is not difficult to envision how this month could have easily verified similarly to 12/77 had a moose fart drifted at a slightly different angle, and the northern stream had synced with that s SW, as opposed to suppressing it.

The moral of the story is that December 2018 was largely anticipated to be frustrating from a snowfall standpoint, or at least it should have. My hunch is that something will work out from about most of sne points northward in latitude as the month begins to draw to a close. This will provide the impetus for some unrealistic expectations for the first half of January, which will engender some feelings of unwarranted disappointment, only to be reinvigorated by the real deal as the month ages and the late January/February bonanza ensues.

Just my two cents-

https://easternmassweather.blogspot.com/2018/12/deceptive-early-season-respite-november.html

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  • 2 weeks later...

Zero changes for January, or the balance of winter for that matter, as previously referenced SSW is underway....still looks to finish slightly above average temps in the aggregate, as laid out in November. Everything remains on track for the window of opportunity for severe winter weather to begin on January 20th through approximately February 20, as originally laid out on November 12th. Absolutely zero has/will be altered or "pushed back". It is in fact guidance that had been trying rush said changes adjusting to better fit the the original date of 1/20, as anticipated. Other forecasters who had been predicting a severely cold month of January in the mean are also scrambling to adjust expectations, which has also clouded the perception of the general populous and is creating unwarranted consternstion amongst winter weather aficionados. It is most unfortunate that this concept is lost on some posters.

Will update with a more precise comparison of December evolution relative to expectation, but the forecast was a success, in contrast to some other outlooks arguing for a harsher onset to boreal winter 2018-2019.

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Here is how the Eastern Mass Weather thoughts laid out on 11/12/18 for the month of December fared.
 
 
December%2BForecast.png
 
"The current scandinavian ridge should retrograde towards Greenland for the first couple of weeks of December, some significant snows are likely for much of New England".
 
NAO.thumb.gif.0c1b15582ea58203b2b55d7a185f0fbf.gif
 
The period of negative NAO did indeed materialize near the onset of the month, but unfortunately the system was forced well to the south of New England by overwhelming confluence.
 
"The PNA may struggle to become established this early, however if it can, the northern mid atlantic may join the fray". 
 
The decline of a robust period of PNA to begin the month coupled with the eroding negative NAO to deliver the goods for the southern mid atl and southeast. 
 
PNA.thumb.gif.e2f4b2036ee6025cc9a2a4b01f0a6ce7.gif
 
 
"The blocking pattern should break down mid month, and there will likely be Grinch storm in the vicinity of Christmas, unlike last season".
 
 
Temperatures should average out near normal for most of the east by month's end, biased colder early, and milder late. If anything, slightly above average for the mid atlantic, and below average in New England".
 
This was a good call, as evidenced by the monthly departure map below, however truth be told, the gradient was a bit further the north across New England than has been anticipated.
 
Dec.thumb.png.492caeccb1212f176e00e56b2f95613b.png
 
Additionally, although a temperature forecast was not put forth for the entire country, the warmth especially across the upper midwest was likely more intense than would have been expected, as the +EPO interlude and associated Pac jet were not expected.
EPO.thumb.png.a3eec73ea9c6553e3756244821a865f0.png
 
 
 
 
This may be due, at least in part, to the MJO amplification through phases 4-6 that was incited by the SSW, which also was unexpected. Although a technical SSW was not forecast, the anticipated evolution for the rest of the winter is not impacted.
In fact, it only serves to further buttress confidence on the emergence of NAO blocking later in the month of January .
 
 
 
January%2BForecaast.png
"The NAO blocking breaks down in time for the holidays, go figure, however around this time the Pacific side grows more supportive, so this mid winter break will not be as prolonged, nor as mild as last season, especially across New England. The month should average anywhere from 1-2 degrees above normal across New England, and 2-3 degrees above normal beneath the 40th parallel. The month of January looks a lot like 2015 and 2005, and we expect a similar evolution. Complete with a monster Archambault event anywhere from January 20th to February 8th, after which the Atlantic couples with the Pacific to induce cross polar flow and set the stage for a memorable February". 
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Mother nature has managed to deconstruct yet another significant winter storm threat with nothing short of surgical precision, as tomorrow's system, which had appeared relatively ominous last week, looks to pass to our north.
FAIL.png

Thus the cold will be once again eradicated not long after precipitation commences, sequence that has become all too familiar throughout boreal winter 2018-2019. And after perhaps an inch of snow near the New Hampshire border, with potentially more in the higher elevations of the Berskshires, followed by a period of icy mix tomorrow, the majority of precipitation will fall as rain, especially from the Connecticut river valley points eastward. Then the attention shifts to next weekend, and as of right now, the region of southern New England looks largely to dodge and weave yet another blow from old man winter. This time the system looks to pass by in the other direction, as the most significant impacts look to remain out to sea, however some light to perhaps moderate snowfall remains possible....especially south and east of Boston.
Both the GFS ensemble suite:
 
Storm%2BGEFS.png


As well as the superior ECWF ensemble mean:
Storm%2BEPS.png
largely concur on the ridge axis being just a bit to far too the east to allow the downstream flow to buckle enough to lift the system all the way up the coast. While the EPS ridge axis is a bit better more favorably positioned to the west for more impacts, it is significantly flatter, thus it is even less favorable in the aggregate than its GEFS counterpart.
Considering the evolution of the first half of the season, it is exceedingly difficult for the beleaguered calvary of winter aficionados to elude the perception of old man winter as an aging middle aged boxer, flailing away in vain during the final moments of a banal career. However old man winter has el nino in his corner, and he may yet be primed to begin landing a succession of devastating blows to local infrastructure once the bell sounds for the second half.
Likely Second Half Blocking Trifecta
Despite the fact that PNA ridging is typically favored during el nino events, it remained relatively elusive throughout December, which is one of the elements that acted to limit snowfall potential easily in the season. This was expected, as specified in the Eastern Mass Weather Winter Outlook that was released on November 12th:
 
PNA%253ARNA.jpg
Negative PNA, vs RNA, Pictured to the Right
"As illustrated above, the positive mode of the PNA favors cool, wet toughing over the east, and milder, drier ridging over the west. Conversely, the negative PNA, or RNA, favor inclement weather in the west, and more pleasant sensible weather in the east. Positive phases of both the PDO and PNA are favored due to the forcing regime associated with this modoki el nino event being centered more over the central Pacific".
Modoki.jpg
 
"However since this particular warm ENSO event is late to develop and still in the process of coupling with the atmosphere, as evidenced by the ONI/MEI and AEI values, the early season period during the month of December is most likely to feature negative phases. Both phases should begin to become biased towards positive as we begin the new year, and the fledgling el nino beings to assert itself".        
                                                            -Eastern Mass Weather 11-12-18
 
Indeed, evidence of the maturation of el nino is beginning to manifest in long term ensemble consensus.
Consensus%2Bon%2BTiple%2BPlay%2BBlocking.png
 
 
Not only are the GEFS and the EPS coming into agreement on blocking over western US, but the recent Sudden Stratospheric Warming and subsequent split of the polar vortex is effectively augmenting typical weak modoki climatology in all but ensuring high latitude blocking both over the Arctic and north atlantic, in the vicinity of Greenland. 
 
 
 
This "blocking trifecta" was evident in the composite of comparable weak modoki events that occurred during a solar minimum, which was presented in the Eastern Mass Weather Winter Outlook
 
"Fortunately, we here at Eastern Mass Weather in our infinite wisdom, have on hand a composite of weak el nino events that occurred in the vicinity of a solar minimum":
 
Temps:
 
 
 
"Note the presence of 1977-1978 on this composite, which is becoming a theme. This season was also a weak modoki el nino with a QBO transitioning into the western shear zone during a solar minimum".
 
Precip:
 
 
 
Note the continued emphasis on Miller B formation in this particular composite.
 
H5:
 
Significant degree of high latitude blocking in the vicinity of Greenland
Our thoughts remain unchanged from the original presentation last November.
 
"The month of January should average anywhere from 1-2 degrees above normal across New England, and 2-3 degrees above normal beneath the 40th parallel. The month of January looks a lot like 2015 and 2005, and we expect a similar evolution. Complete with a monster Archambault event anywhere from January 20th to February 8th, after which the Atlantic couples with the Pacific to induce cross polar flow and set the stage for a memorable February. 
 
 
 
 
 
 
 
"What a tremendous difference a year makes. Winter's main course is where it should be climatologically speaking, during February. The sky is the limit for wintery potential this month, as this is as favorable it as it precarious as it gets, not at all unlike February 1978. This is the window for the mid atlantic to see major storm, especially if el nino grows a bit more potent than forecast. However odds favor the most crippling OF impacts being confined to New England. Intense blocking over Greenland, the pole, as well as Alaska and northwestern Canada. The second window for a historic event adjoins the first window, from February 9th through February 20th. After which the pattern relaxes and blocking relents somewhat. The northeast should average 2-4 degrees below average, and the mid atlantic 3-6 degrees below average".
 
 
 
 
 
"Blocking may not persist as strongly through March as the model implies, as this portion of the forecast is lower confidence. The PNA looks to wane, and there is very high confidence that the robust negative EPO will remain for the entire winter. Although this is another favorable regime for cold delivery, the source will likely be depleted by this point, and some moderation will be the rule as the airmass grows stale. The month should average  out near normal across the mid atlantic, and 1-2F degrees above average throughout New England".
 
 
-Eastern Mass Weather 11-12-18
 
In closing, here is a list of snowfall through yesterday, January 6, for Boston during some of the most prominent modoki el nino analog seasons. Followed by eventual seasonal totals to the right.
2015: 4.5"    110.6"
2005: 18.0"  86.6"
1978: 9.7"   85.1"
1969: 6.0"    53.8"
 
2018: .2"  ?
 
Eastern Mass Weather snowfall forecast and prognostications for aggregate December through March readings of some prominent atmospheric indexes.
 
 
 
 
 
 
Index Value
Predicted '18-'19 DM Value Range
Actual  '18-'19 DM Value
Departure From Verification
Pacific Decadal Oscillation (PDO)
.40 to .70
 
 
Perennial North American Pattern (PNA)
.25 to .55
 
 
ENSO
Weak Modoki El Nino (0.9 to 1.1C ONI) (DJF)
 
 
 (J-M) East Pacific Oscillation (EPO)
-1.20 to -1.50
 
 
Arctic Oscillation (AO)
-.35 to -.60
 
 
North Atlantic Oscillation (NAO)
-.10 to -.35
 
 
 
 
 
 
 
City
Predicted Snowfall
Actual
Percent Departure From Forecast Range
Boston, MA (BOS)
80-90"
 
 
New York, NY (CPK)
40-50”
 
 
Philadelphia, PA (PHL)
35-45”
 
 
Baltimore, MD (BWI)
20-30”
 
 
Washington, DC (DCA)
15-25”
 
 
Albany, NY (ALB)
75-85”
 
 
Hartford, CT (BDL)
65-75”
 
 
Providence, RI (PVD)
55-65"
 
 
Worcester, MA (ORH)
90-100”
 
 
Tolland, CT (TOL)
80-90”
 
 
Methuen, MA
90-100”
 
 
Hyannis, MA
45-55"
 
 
Portland, ME (PWM)
85-95"
 
 
 Burlington, VT (BTV)
 85-95"
 
 
Concord, NH (CON)
 
 
75-85”
 
 
 
 
 
 
 

 

Posted 16 hours ago by Raymond Spinazola
 
  
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  • 1 month later...
Yet another bundle of energy trundles up into the mid latitudes well to out west and through the great lakes this weekend, rinse and repeat. This promises to be an even warmer evolution from what we witnessed on Wednesday night, as the antecedent airmass will not be as cold, thus will put up less resistance to the the southwesterly flow aloft eradicating it.
Synoptic%2B1.png
Energy will continue to focus to your west, thus limiting snowfall until either:
1) A ridge of high pressure develops over the west coast, causing the energy to dig southward.
2) High latitude blocking materializes in the vicinity of greenland and the Davis straight, which would force the energy south, as well.

A very cold antecedent airmass can mitigate this somewhat, and fore a redevelopment to the east, near the coast. This is what took place on Wednesday night. However since the airmass in place over the area this weekend is not very cold, the low in the mid levels is not transferring to the coast until it is past our latitude.
Synoptic%2B2.png
Thus the ski areas are saved. Sound familiar? Perhaps locales to the north of the Mass pike in our region will see a few flakes near the onset.
Regional Evolution
Note that as the precipitation begins later tonight and early Sunday morning, temperatures in the mid levels of the atmosphere are already approaching the freezing point, which greatly limits any potential accumulations to primarily north of the Mass/New Hampshire border, which will be quite light at that.
Flip.png
 
The precipitation only runs in advance of the mid level warmth by a very slim margin. Ice should not be much of an issue since the low level cold will not be as impressive of as tenacious as Wednesday night.
On Thursday when the First Call was made, it appeared as though there could be some slight accumulations north of the Mass pike.
First Call, issued 11pm Thursday.
First%2BCall.png
However it now appears as though most accumulation will be relegated to central and northern New England.
Final Call:
Rainy%2BFinal%2BCall.png
 
At this point, it is entirely fair to question whether some of the energy that has been ejected into the west all season long will ever begin making to the east coast to produce a coastal system.
More of the Same Ahead
In a complete reversal from this fall, the short answer from Eastern Mass Weather is "no". While it is possible that there may yet be significant snowfalls for the area, which climo dictates that there will be, we still see no signs of either significant east coast ridging, or north atlantic blocking.
Here is the latest European ensemble suite.
More%2Bof%2Bthe%2BSame.png
It is noted that while some semblance of a PNA ridge out west attempts to develop, it remains both fleeing and insufficient to prevent jet energy from consolidating and digging too far to the west. While the European suite is not infallible, and has in fact led us astray many times this season, there exists no "smoking gun" or impetus for change. One of the most ineffective el nino events on record is waning, and there are no signs that the polar stratosphere will warm. What went "wrong" will be discussed more extensively in this spring's outlooks verification analysis, however we believe that the Sudden Stratospheric Warming event that took place early this season was quite different from the one that led to last season's record March snows. And it ultimately worked to enhance factors inimical to high latitude blocking this season, and act as a source of deconstructive interference for mechanisms that would have assisted in the development of blocking otherwise. Eastern Mass Weather not only failed to foresee the development of a sudden stratospheric warming this season, but it was also poorly diagnosed once it became obvious that one would occur. It was this, in conjunction with an el nino that never really manifested itself into the tropical forcing, that proved fatal to the success of the winter outlook.  While we correctly diagnosed the meager ability of the el nino to impart an influence on the tropical forcing regime and hemispheric pattern, as evidenced by the recognition of the paltry MEI and inclusion of the 1969 analog, we interpreted this as affirmation that the event would remain weak, and thus favorable for increased blocking and southern New England snows. However instead of asserting itself as weak events typically do, it never asserted itself at all, thus there was no impetus for a change from the residual la nina forcing from 2018. We believe that this also took place in 1969, on the heels of a cool-neutral ENSO winter, however intense blocking proved instrumental in the historic February that evolved across the area. It is believed that the recovery of the polar vortex in the wake of the SSW that took place on New Year's day proved fatal to the development of any blocking as the second half of the season evolved. And since the SSW was centered on the other side of the globe, and not over the north atlantic, it only served to enhance the residual la nina like intraseasonal MJO signal, which also proved inimical to the development of blocking.
In Summary:
1) El Nino peak ONI was well forecast, however the implications of the meager MEI that was correctly deemed as analogous to 1969 was poorly diagnosed as proof that el nino would remain weak. It was non existent, thus the residual la nina intraseasonal MJO signal was enhanced.  We believe that this was intimately connected to the poorly forecast and poorly diagnosed SSW.
2) Eastern Mass Weather did recognize the November Scandinavian blocking as a precursor to a season with a great proclivity for poleward heat flux/transfer...another parallel to 1969. We simply interpreted this as a BIG indicator for blocking. However this may have worked out TOO well. A SSW was NOT expected, but one did occur near the onset of the New Year. First of all, this probably served to shorten the duration of the favorable early December period, as the period preceding SSW events is usually hostile too blocking. Additionally, once it materialized,  the problem was that unlike last season, this SSW was not focused over the north atlantic, but rather the other side of the globe. Thus it did NOT promote NAO blocking, but instead amplified the hostile MJO, which due to no show el nino, was mired in la nina like phases like 1969. This also set up the recovery of the PV, which in conjunction with la nina like MJO worked to deconstructively interfere with second half blocking typical of weak modoki el nino seasons. 
 
It was a very flawed outlook that still provided plenty of instructional value, thus it will benefit future outlooks. Unfortunately, that if of little solace to southern New England snow lovers this season.
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