Countdown to Winter 2017-2018 Thread

[tamarack]

6 minutes ago, Typhoon Tip said:

Well ... in any case ... "true" end-to-end winters are exceptional -

Will, it may just be my personal climate experience on matters, but I don't really think of Apr as being "fairly" include-able though - even as a shoulder month. 

We have snow from time to time in that month... but so as could be said about May's in general, just "supposedly" much rarer.  We wouldn't count on May as a book-end value.  I think of April as just a throw away month ... really. It's like the climate time forgot; the actual physical universe just gave up, threw hands, and let Satan do as it will with that month because come hell or high water ...it always finds a way to disappoint weather enthusiasts of both hot and cold focus.  

Haha.  Seriously though, I would include March as the ending shoulder... But, you know - our sub-forum includes NNE ...even though we distinguish it inside our realm.  And April is fairly their shoulder month.  Perhaps RUT-CON line is March 15 to April 15, and down here is March.  

The only way to really be scientific is to do some sort of tercile statistical correlation between the three, cold --> misery mist --> hot, with the last dates of frost and average snows being the focus of the study - maybe start there. 

Have to agree about April, though if I still lived in Ft. Kent I might argue a bit.  However, where I am now April snow is hit or miss, mostly the latter.  In 19 years I've measured only 4 April snows greater than 4", one in 2011 (15.1") and 3 in 2007 (18.5", 11.2", and 5.2" with 5" RA in the Patriot's Day storm.)  Those two Aprils brought more snow than the other 17 combined.  Kind of like 1982 and 1996 farther south.  November is similar for large snowfalls, though a bit less stochastic for monthly totals.

[Typhoon Tip]

1 hour ago, tamarack said:

Have to agree about April, though if I still lived in Ft. Kent I might argue a bit.  However, where I am now April snow is hit or miss, mostly the latter.  In 19 years I've measured only 4 April snows greater than 4", one in 2011 (15.1") and 3 in 2007 (18.5", 11.2", and 5.2" with 5" RA in the Patriot's Day storm.)  Those two Aprils brought more snow than the other 17 combined.  Kind of like 1982 and 1996 farther south.  November is similar for large snowfalls, though a bit less stochastic for monthly totals.

yeah bottom line ...it's a S-N in spring, N-S in autumn spectrum.  

 

[J.Spin]

3 hours ago, Typhoon Tip said:

 But, you know - our sub-forum includes NNE ...even though we distinguish it inside our realm.  And April is fairly their shoulder month.  Perhaps RUT-CON line is March 15 to April 15, and down here is March.

 

2 hours ago, tamarack said:

Have to agree about April, though if I still lived in Ft. Kent I might argue a bit. 

 

At least here in the Northern Greens, I think it works out fine using November and April as the relevant shoulder months for inclusion in “winter”, for at least a few of reasons.  First, there’s the front-end/back-end seasonal symmetry and consistency I see in my snowfall data.  November and April snowfall averages here are 10.5” and 6.4” respectively, so November gets a bit of a nod in terms of snowfall, but they both nicely represent similar demarcations from the hefty winter months of December through March with the much more substantial 25”-40” snowfall averages.  Of the 22 Novembers or Aprils I have in my data set, only 1 (November 2006) lacked accumulating snow, so there’s a degree of consistency there as well, and it sounds like November is less of a concern here anyway.

 

Additionally, there’s the mountain factor.  One can lock their seasonal perspective to a specific observations site for the strictest objective analysis, but for the most part, people’s lifestyles and recreation are intimately linked with the mountains here, so what happens in the middle and high elevations matters in the overall perception of the winter season.  If November and April are arguably the shoulders in the valleys, then they definitely qualify in the mountains.

 

Using a whole shoulder month’s snowfall/snowpack data as inclusion in winter assessment may be a bit coarse, but there’s a benefit to having it that way vs. selecting a specific cutoff date.  It gives one a free buffer in the assessment for events/stats that may flirt with a more rigorous cutoff.  Sure, the first 10 days of November and last 10 days of April may be the least relevant in terms of snowfall or what have you, but for additive elements like snowfall amount, snowpack, days with snow, etc., they generally don’t effect the numbers, so whether they are included or not, it doesn’t matter.  For the occasional times when something of importance happens during those periods, they bolster the character of that month a bit, as they should.

[Typhoon Tip]

24 minutes ago, J.Spin said:

 

 

Using a whole shoulder month’s snowfall/snowpack data as inclusion in winter assessment may be a bit coarse, but there’s a benefit to having it that way vs. selecting a specific cutoff date.  It gives one a free buffer in the assessment for events/stats that may flirt with a more rigorous cutoff.  Sure, the first 10 days of November and last 10 days of April may be the least relevant in terms of snowfall or what have you, but for additive elements like snowfall amount, snowpack, days with snow, etc., they generally don’t effect the numbers, so whether they are included or not, it doesn’t matter.  For the occasional times when something of importance happens during those periods, they bolster the character of that month a bit, as they should.

It's whenever the steepest slope time is for snow fall... 

Take 120 years worth of spring and autumns: what 30 day period slopes' average steepest - that's your shoulder at that location.  I think March 1 to April 1 ...I bet that's about right for Worcester Mass... But up in Allagash Maine it would be later. 

 

[J.Spin]

22 hours ago, Typhoon Tip said:

It's whenever the steepest slope time is for snow fall... 

Take 120 years worth of spring and autumns: what 30 day period slopes' average steepest - that's your shoulder at that location.  I think March 1 to April 1 ...I bet that's about right for Worcester Mass... But up in Allagash Maine it would be later. 

LOL, the degree to which meteorologists not only consider such minutiae but have actually mathematically formalized them, never ceases to amaze me.

 

Anyway, I do have the daily snowfall means for my site, so I figured I’d run the analysis.  First off, I thought it would be nice to actually have a visual representation of the daily snowfall means for some perspective on the data, so I plotted that below.  As you can see, even after 11 seasons, the daily snowfall means are still quite noisy, so I had Excel add a trend line for a 30-day moving average, which at least gives one an idea of where things might settle in with more data.

 

 

Although unfortunately contributing to the noise, one fun perk derived from the plot is that individual outliers on the high end are actually products of some of our area’s more memorable storms.  The storms associated with the creation of the three highest daily snowfall means are:

 

1. Valentine’s Day Storm (2007)

2. Winter Storm Stella (2017)

3. Feb 24-25 NNE Secondary Cyclogenesis & Upslope (2012)
    

The origins of the higher points begin to get a bit more muddled after that, but some are still very clearly derived from an individual storm, such as the December 26^th-27^th, 2012 storm, which wasn’t especially large here (15.5”), but it had an impact on the data because all the snow essentially fell in one calendar day.

 

So to get at the shoulders of the season, at least based on Tip’s definition and my understanding of it, I had Excel perform linear regressions and output the resulting slope for each 30-day segment of the snowfall season.  Next, to avoid having to search through all those resulting slopes by eye, I had Excel independently rank the resulting slopes for the first half (generally positive) and second half (generally negative) of the season.  Despite the noise in the data, I’d say the results were fairly robust because the dates with the steepest slopes were clearly clustered at two specific locations – the 3 to 5 highest values were sitting right next to each other.

 

So for a visual, the 30-day slope data are plotted below by date according the last day of the segment.  I actually took the absolute values of the slopes and plotted those, to remove negative numbers and simplify the plot.

 

 

So, using those numbers, it would put the 30-day “shoulder periods” of the snowfall season here at Nov 10 – Dec 9 for the fall side and Mar 14 – Apr 12 for the spring side.  I was sort of surprised at how much of November is pulled into that shoulder season based on this analysis (vs. the perception of how slowly November snowfall seems to get rolling sometimes), but if going by whole months, it’s clearly got the nod with respect to inclusion over April.  April’s still got a decent chunk of itself in the snowfall season though, even down here in the valley, so in line with the thoughts from my previous post, I don’t think it’s too outrageous to throw it into the mix when assessing the winter around here.  If the local mountains are being considered in the winter narrative, April really gets a boost in importance as well.

[Typhoon Tip]

29 minutes ago, J.Spin said:

LOL, the degree to which meteorologists not only consider such minutiae but have actually mathematically formalized them, never ceases to amaze me.

 

Anyway, I do have the daily snowfall means for my site, so I figured I’d run the analysis.  First off, I thought it would be nice to actually have a visual representation of the daily snowfall means for some perspective on the data, so I plotted that below.  As you can see, even after 11 seasons, the daily snowfall means are still quite noisy, so I had Excel add a trend line for a 30-day moving average, which at least gives one an idea of where things might settle in with more data.

 

 

Although unfortunately contributing to the noise, one fun perk derived from the plot is that individual outliers on the high end are actually products of some of our area’s more memorable storms.  The storms associated with the creation of the three highest daily snowfall means are:

 

1. Valentine’s Day Storm (2007)

2. Winter Storm Stella (2017)

3. Feb 24-25 NNE Secondary Cyclogenesis & Upslope (2012)
    

The origins of the higher points begin to get a bit more muddled after that, but some are still very clearly derived from an individual storm, such as the December 26^th-27^th, 2012 storm, which wasn’t especially large here (15.5”), but it had an impact on the data because all the snow essentially fell in one calendar day.

 

So to get at the shoulders of the season, at least based on Tip’s definition and my understanding of it, I had Excel perform linear regressions and output the resulting slope for each 30-day segment of the snowfall season.  Next, to avoid having to search through all those resulting slopes by eye, I had Excel independently rank the resulting slopes for the first half (generally positive) and second half (generally negative) of the season.  Despite the noise in the data, I’d say the results were fairly robust because the dates with the steepest slopes were clearly clustered at two specific locations – the 3 to 5 highest values were sitting right next to each other.

 

So for a visual, the 30-day slope data are plotted below by date according the last day of the segment.  I actually took the absolute values of the slopes and plotted those, to remove negative numbers and simplify the plot.

 

 

So, using those numbers, it would put the 30-day “shoulder periods” of the snowfall season here at Nov 10 – Dec 9 for the fall side and Mar 14 – Apr 12 for the spring side.  I was sort of surprised at how much of November is pulled into that shoulder season based on this analysis (vs. the perception of how slowly November snowfall seems to get rolling sometimes), but if going by whole months, it’s clearly got the nod with respect to inclusion over April.  April’s still got a decent chunk of itself in the snowfall season though, even down here in the valley, so in line with the thoughts from my previous post, I don’t think it’s too outrageous to throw it into the mix when assessing the winter around here.  If the local mountains are being considered in the winter narrative, April really gets a boost in importance as well.

Nice presentation!

firstly...  well, Meteorology is a science, so... stands to reason those of us that had college work beaten over our heads like an angry empirical nun brandishing a ruler are probably prone to setting up things up in that way.  

secondly... yeah, that's basically what we were thinking... about November to April up your way.  

I'm actually intrigued by the mid season dip... I almost wonder if those are related to the typical Rosby timing for pattern reloads and the advent of either thaws or just indirectly related calm periods.  interesting...  In 1995 (which ironically started this discussion), we had a similar abeyance of winter in mid stride, only to reload pretty heavily after that two to three week interlude.  

[tamarack]

23 hours ago, Typhoon Tip said:

It's whenever the steepest slope time is for snow fall... 

Take 120 years worth of spring and autumns: what 30 day period slopes' average steepest - that's your shoulder at that location.  I think March 1 to April 1 ...I bet that's about right for Worcester Mass... But up in Allagash Maine it would be later. 

 

Only 25 years of record at Allagash (1986 thru early 2011) so I went to CAR, records beginning in 1939, using numbers of 6"+ snowstorms to track late season "shoulder slope."

                       6"+   8"+   10"+   12"+
March 1-15      56     39      20      14
March 16-31    27     17      12       6
April 1-15        20      9        5       1  (1982, with 26.3")
April 16-30        5      2        1       0

By 5-day per.  1-5    6-10  11-15
March 1-15      15      23      18

                   16-20  21-25  26-31  (none on 3/31)
March 16-31    14       7         6

                     1-5    6-10  11-15
April 1-15         9        7         4

                   16-20  21-25  26-30 
April 16-30        2        1        2

I'd put CAR's shoulder at March 21 thru April 15 (or the 13th, as the 4 storms in the 11-15 bracket came on the 11th or 13th.)   March thru the 20th is still midwinter there, at least by storm numbers, and late April is more fingertips than shoulder.

[J.Spin]

17 hours ago, Typhoon Tip said:

I'm actually intrigued by the mid season dip... I almost wonder if those are related to the typical Rosby timing for pattern reloads and the advent of either thaws or just indirectly related calm periods.  interesting...  In 1995 (which ironically started this discussion), we had a similar abeyance of winter in mid stride, only to reload pretty heavily after that two to three week interlude.  

 

Anecdotally, I want to just blame it on the old “too cold to snow” phenomenon, where the storm track gets pushed a bit too far south at the peak of the winter season, and we’re left high and dry up north in the arctic air.  I don’t specifically have the data to support that premise, that’s just the way it’s “felt” over the seasons since I’ve been back in NVT.  It’s also possible that those cold and dry periods are simply more memorable for me.

 

January is the peak snow month (barely, behind Dec/Feb) and lowest temperature month (barely, behind Feb) for BTV.  So, our local first-order station about 20 miles away doesn’t show any January snowfall dip.  That’s not to say that the area where I’m located, which exhibits dramatic differences in precipitation, temperatures, upslope snow, etc. from BTV, has to follow suit.  But the proximity will no doubt represent some similarities in climate.

 

I don’t personally track temperature data at my site, but I do have precipitation data.  January is the driest month of the year in my data, with a 31% drop in liquid relative to the surrounding months of Dec/Feb.  There’s also a 16% drop in snowfall here relative to those months.  Interestingly, Feb is the driest month in the BTV data.

 

Is the January snowfall dip simply a result of my relatively small data set?  Hopefully I can keep the data going and time will tell.

[Typhoon Tip]

2 hours ago, J.Spin said:

 

Anecdotally, I want to just blame it on the old “too cold to snow” phenomenon, where the storm track gets pushed a bit too far south at the peak of the winter season, and we’re left high and dry up north in the arctic air.  I don’t specifically have the data to support that premise, that’s just the way it’s “felt” over the seasons since I’ve been back in NVT.  It’s also possible that those cold and dry periods are simply more memorable for me.

 

January is the peak snow month (barely, behind Dec/Feb) and lowest temperature month (barely, behind Feb) for BTV.  So, our local first-order station about 20 miles away doesn’t show any January snowfall dip.  That’s not to say that the area where I’m located, which exhibits dramatic differences in precipitation, temperatures, upslope snow, etc. from BTV, has to follow suit.  But the proximity will no doubt represent some similarities in climate.

 

I don’t personally track temperature data at my site, but I do have precipitation data.  January is the driest month of the year in my data, with a 31% drop in liquid relative to the surrounding months of Dec/Feb.  There’s also a 16% drop in snowfall here relative to those months.  Interestingly, Feb is the driest month in the BTV data.

 

Is the January snowfall dip simply a result of my relatively small data set?  Hopefully I can keep the data going and time will tell.

Yeah ...that (bold) actually makes a good deal of Meteorological sense ... The ambient polar boundary vacillates from N to S ...then S to N across the seasonal migration as kind of a Climate-101 facet.  Then understanding that the storm track tends to migrate along with that is part of what that means.  

It sort of engenders another question related to the effects of GW on the ambient position of these known features/their behaviors throughout the year/seasons.  For example, the if the polar boundary tends to migrate from eastern Canada to perhaps the Mid Atlantic (say...), in a warming world, would the bottom latitude extent be the case?   Climate modeling as it pertains to this GW phenomenon has been indicating that the snow and cold latitude bands will migrate N along the eastern seaboard as the world warms.  So, given a few decades (depending on the rapidity of that change) that "dent" in mid stride would tend to fill perhaps?   I mean, if the mid winter boundary doesn't bottom out as far S, then that might over time favor your region... But, it could also change the numbers at the 'shoulders' too -

[CoastalWx]

Wow that's a great graphic. I'm sure the dip in mid winter may related to storm track and resulting temps. Generally warmer air holds more moisture, and I see that phenomenon in your upslope events....which accounts for quite a bit of your snowfall. So I am not surprised at the dip....although even 11 seasons can be a short sample size. 

[Typhoon Tip]

11 minutes ago, CoastalWx said:

Wow that's a great graphic. I'm sure the dip in mid winter may related to storm track and resulting temps. Generally warmer air holds more moisture, and I see that phenomenon in your upslope events....which accounts for quite a bit of your snowfall. So I am not surprised at the dip....although even 11 seasons can be a short sample size. 

Yep... very inclined to agree - ... 

[mreaves]

42 minutes ago, CoastalWx said:

Wow that's a great graphic. I'm sure the dip in mid winter may related to storm track and resulting temps. Generally warmer air holds more moisture, and I see that phenomenon in your upslope events....which accounts for quite a bit of your snowfall. So I am not surprised at the dip....although even 11 seasons can be a short sample size. 

PF has been saying that for years and he gets told don't worry as long as its cold.  We can deal with average to slightly above average temps we need the moisture up here.

[CoastalWx]

Just now, mreaves said:

PF has been saying that for years and he gets told don't worry as long as its cold.  We can deal with average to slightly above average temps we need the moisture up here.

But since he gets much of his snow from upslope, it may be due to that and not necessarily storm track? You have to dig even further to determine if it is more of a synoptic issue..vs mesoscale like uplsope.

[mreaves]

Just now, CoastalWx said:

But since he gets much of his snow from upslope, it may be due to that and not necessarily storm track? You have to dig even further to determine if it is more of a synoptic issue..vs mesoscale like uplsope.

For his location maybe but for those of us away from the upslope zone its different. I would also think there is the same correlation there but maybe to a lesser extent.

[ORH_wxman]

Just now, mreaves said:

For his location maybe but for those of us away from the upslope zone its different. I would also think there is the same correlation there but maybe to a lesser extent.

Well nearby non-upslope BTV doesn't have a dip in January snowfall...much longer period of record. So I'd say the data is inconclusive on that front given that it contradicts jspin's data. They are different climates (but similar latitude).

[mreaves]

Just now, ORH_wxman said:

Well nearby non-upslope BTV doesn't have a dip in January snowfall...much longer period of record. So I'd say the data is inconclusive on that front given that it contradicts jspin's data. They are different climates (but similar latitude).

You mean my completely anecdotal observations and feelings don't stack up to scientific observations? 

[ORH_wxman]

27 minutes ago, mreaves said:

You mean my completely anecdotal observations and feelings don't stack up to scientific observations? 

Haha...just ask powderfreak how bad -NAO winters are for snowfall in Stowe. He will tell stories around the campfire for hours.

[J.Spin]

2 hours ago, CoastalWx said:

Wow that's a great graphic. I'm sure the dip in mid winter may related to storm track and resulting temps. Generally warmer air holds more moisture, and I see that phenomenon in your upslope events....which accounts for quite a bit of your snowfall. So I am not surprised at the dip....although even 11 seasons can be a short sample size. 

 

I was looking back at the daily snowfall plot during the discussion, and realized that the moving average seemed a bit delayed relative to what I would expect (the midwinter snowfall dip should really be centered around mid to late-January, not early February).  I noted that it was because I let Excel calculate the 30-day moving average as an automated trend line, and it plots the average on the last day of the 30-day period.  For best visualization of the data, I’d really prefer that it plot the 30-day average on the middle date of the 30-day period, so I calculated the values manually and fixed the trend line.  The data are the same, just shifted roughly 15 days earlier.  Now the trend line for snowfall ramps up more like I’d expect in November, hits the nadir of the dip around January 20^th in line with the individual data points, and the snowfall trend line doesn’t linger so long in April.  I updated the plot on my server and flushed the cache there, but I’m not sure how long it would take to propagate to the file visualized here.  I inserted a new copy in this post as well to hopefully catch the updated version.

 

[J.Spin]

Well, the old version of the plot is still showing up here on AmWx for me, but one can use the direct link to the file on my server, and that should present the updated image:

 

http://jandeproductions.com/2017/meandailysnowfall.jpg

[SnowHole413]

well the qbo is officially negative now. Currently reads at a -3.18. That's a good thing for next winter but, does anyone know if its a bad thing if it's super negative? Such as a -20 or more? 

[CoastalWx]

On 7/5/2017 at 2:11 PM, Powderboy413 said:

well the qbo is officially negative now. Currently reads at a -3.18. That's a good thing for next winter but, does anyone know if its a bad thing if it's super negative? Such as a -20 or more? 

Not sure you can quantify effects based on a numerical value. Kind of like ENSO. You can get effects you don't expect from whatever 3.4 is, despite the anomalies.  I think normally what matters is the trend of whatever you are trying to quantify, because that's when the atmosphere is adjusting. 

[Typhoon Tip]

2 hours ago, CoastalWx said:

Not sure you can quantify effects based on a numerical value. Kind of like ENSO. You can get effects you don't expect from whatever 3.4 is, despite the anomalies.  I think normally what matters is the trend of whatever you are trying to quantify, because that's when the atmosphere is adjusting. 

Also ... if perhaps even in support of that thinking ...  there's a indicative conflict of conception/science and thus operational reasoning in using QBO for winters.  Call it a mild contradiction. 

I once saw a presentation at one of those weather "comic-cons" the greater ambit of Meteorology refers to as conferences ...  It was given by ....Florida State. I cannot for the life of me recall the Dr.'s name at the moment ... But, he demonstrated both a-priori (sort of anecdotal),  as well as empirical evidences (statistical) showing there is a connection between west Atlantic frequency of re-curving tropical cyclones between preceding autumns, and subsequent tendency for +NAO phase state.. 

That long words for:  +NAO most of the time in winters after repeated autumn hurricanes only managed to successively break the hearts of zealot storm dorks. 

The implicit physical argument there (if I recall right) was that the feed of latent heat into the on-going, larger scaled vortex ...  sort of keeps the NAO sub-polar gyre energized and active/anomalously strong... That is of course the +NAO phase state - the study didn't say anything about west or east -based; though that would be an interesting sub-study. 

However, that leads me to ponder ... If the negative QBO phase state correlates with increased TC frequency and intensity in the west Atlantic, but it also is correlated with stronger -AOs in descending winter months ... do you see the conflict there?

Simple conjecture FOR THE GENERAL READER to offer some reconciliation:

Well ...1st, there is  disconnect between the AO and NAO.  These fellow index domain spaces only share portions of their respective geographies.  The AO is pretty much the circular region above the 60th parallel.. as pretty much a numerical representation of the planetary Polar Vortex. -4 means a very weak vortex; +4 is Jovian!  Basically, plunk a doughnut of whirling air down over the geographic North Pole that extends to about the top of Jame's Bay's latitudes... then measure it using Empirical Orthogonal Functions when a telephone call to Barrow Alaska all along may have sufficed. The NAO only shares the AO spatial dimension over it's northern arc. 

This disparity could actually stop the discussion ... come to think about it. Because we have seen many, many times in the past scenarios where that disconnect played out:  -AO/+NAO phase couplets... It's just that by proxy and proximity combined, they would "tend" to be more positively correlated (move together).  Hmm.  Imagining a winter with -AO while simultaneously maintaining a +NAO.re-curve driven anomaly ... I bet that would be bad... You'd end up with -AO cold loading with a strong "hook" over eastern Canada to grab it and drill it SE... Get the EPO negative then we're really partying.

2nd one being, increased frequency of west Atlantic TC's can happen without re-curving behavior.  The question then becomes, should the correlation be more in line with the "behavior" of storm motion, or the "existence" of the TCs.   In either case, where does the latent heat flux go?  It's still going to be lifted to higher latitudes by the on-going maelstrom of the Earth's greater balancing.. Whether those latent heat fluxes migrate N as shredded globs of atmospheric mass, or are inserted more directly as a TC strafing NS while NE licks wounds of 30 cycles of GFS clocking LI ... it's all destine to be ingested into the majestic mechanics of the SPV/NAO. So, perhaps the causality is dubious.  Seems like the more one digs with thought experimentation, the more complex the system gets as you have to keep adding variables that cannot be discounted.  

This would might offer a way out of the mild contradiction... If the QBO could somehow be subsequently correlated with recurving behavior ...versus say Caribbean cruisers and Katrina's ... it may "fit" with the disconnection with the AO and NAO.  That would be fascinating -

 

[JBinStoughton]

On 7/5/2017 at 2:11 PM, Powderboy413 said:

well the qbo is officially negative now. Currently reads at a -3.18. That's a good thing for next winter but, does anyone know if its a bad thing if it's super negative? Such as a -20 or more? 

During winterzilla a couple years ago it was very negative but we had other teleconnectors that were different than now. Who knows. In any event it's gotta be better than the positive we've had the last two winters that seemed to ruin everything. 

[weathafella]

23 hours ago, JBinStoughton said:

During winterzilla a couple years ago it was very negative but we had other teleconnectors that were different than now. Who knows. In any event it's gotta be better than the positive we've had the last two winters that seemed to ruin everything. 

What were your snow totals the past 2 seasons?  It seems like they couldn't be too far vs normal?

[CoastalWx]

25 minutes ago, weathafella said:

What were your snow totals the past 2 seasons?  It seems like they couldn't be too far vs normal?

He was near normal 15/16 and AN 16/17

[weathafella]

Just now, CoastalWx said:

He was near normal 15/16 and AN 16/17

He described those winters as "ruined".   100" or bust I guess...

[ORH_wxman]

1 hour ago, weathafella said:

He described those winters as "ruined".   100" or bust I guess...

Well after 2014-2015...they all kind of suck. Lol.

 

The interior was kind of crappy in 2015-2016...a lot worse than the coast. ORH didn't even crack 50"...but BOS was 36.1" which is only a little bit below normal. I think sometimes we need to remember how big the standard deviation of snowfall is around here. BOS has an SD of like 22" in one season, so really anything between 34-54" should probably be considered "normal" if we are chopping up a half standard dev across the mean. The BOS snowfall distribution (and all of our sites actually) of course is not a totally normal distribution either...we get values that are 60"+ above average, but we don't get anything more than about 35" below average.

 

Either way, we're probably due for some regression....the first 7 years of this decade have produced an average of 58.1" of snow per season at BOS...and a median of 58.9". That's coming on the heels of the 2000-2001 to 2009-2010 decade which averaged 46.9" at BOS....which is coming on the heels of the 1990-1991 to 1999-2000 decade which averaged 48.2" at BOS. Man, what a spoiled period. In fact, in the past 27 winters since 1990-1991, BOS is averaging 50.3" of snow. The new climate normals in 2020 are gonna have to up the average.

[tamarack]

On ‎6‎/‎30‎/‎2017 at 1:39 PM, ORH_wxman said:

Well nearby non-upslope BTV doesn't have a dip in January snowfall...much longer period of record. So I'd say the data is inconclusive on that front given that it contradicts jspin's data. They are different climates (but similar latitude).

Entering this subject late - my 19 winters show a slight dip in mid January (and run significantly below J.Spin's averages, especially early in the season.)  The daily average (a 15-day mean, centered on the subject date) climbs from 0.28" on 11/29 to 0.7" by Dec. 11, fueled by events like the 24" on 12/6-7/03.  The average stays right around 0.7" thru Jan. 6, then dips to the 0.60" range for the next 3 weeks (Jan. 7-28.)  Then it climbs to its peak on Feb. 6-9, a 4-day span averaging just under 1" - top day is the 7th with 1.01".  Feb. 2-20 is the 0.80+ stretch, followed by a steady decrease to under 0.4" by the end of March, thence to zero.  (Latest I've maintained continuous cover is 4/23/01.)

The January dip is driven by the lack of big storms and big months.  Below are Nov/April numbers, first for 10" storms (33 total) then for 30" months (21 total.)

10"+ storms:  1, 8, 3, 8, 10, 3  Peak is March, Jan same as April

30"+ months:  0, 6, 1, 9, 4, 1   Peak is Feb, Jan same as April

[powderfreak]

5 hours ago, CoastalWx said:

He was near normal 15/16 and AN 16/17

There's definitely some skewed perception...likewise up here I thought last winter was the best thing since sliced bread just because we got above normal snow, forget retention or low el snowpack.  

We got spoiled by 2000-2011 and then entered a string of tougher winters that weren't even that bad, a bit below normal except for 15-16 which was record bad...but coming off a good streak those winters of like 80% of normal seem much worse than they should be.

[ORH_wxman]

2 hours ago, tamarack said:

Entering this subject late - my 19 winters show a slight dip in mid January (and run significantly below J.Spin's averages, especially early in the season.)  The daily average (a 15-day mean, centered on the subject date) climbs from 0.28" on 11/29 to 0.7" by Dec. 11, fueled by events like the 24" on 12/6-7/03.  The average stays right around 0.7" thru Jan. 6, then dips to the 0.60" range for the next 3 weeks (Jan. 7-28.)  Then it climbs to its peak on Feb. 6-9, a 4-day span averaging just under 1" - top day is the 7th with 1.01".  Feb. 2-20 is the 0.80+ stretch, followed by a steady decrease to under 0.4" by the end of March, thence to zero.  (Latest I've maintained continuous cover is 4/23/01.)

The January dip is driven by the lack of big storms and big months.  Below are Nov/April numbers, first for 10" storms (33 total) then for 30" months (21 total.)

10"+ storms:  1, 8, 3, 8, 10, 3  Peak is March, Jan same as April

30"+ months:  0, 6, 1, 9, 4, 1   Peak is Feb, Jan same as April

Your data seems to match jspin with the jan dip...although it should be noted that it is also a relatively short sample unlike the BTV sample which didn't show a dip but was also 100+ years worth. It seems like January has been a harder month to get big snows up there in the past 15-20 years. That would be in contrast to down here...ORH has seen 5 of the last 15 Januarys produce 20"+ and 3 of them produce 40"+ including a 50"+...more importantly though, only 4 of the 15 have been below average, so the non-20"+ Januarys have been in that 14-18" range keeping it a decent month. Of course, that pales in comparison to February which has been 10 out of the last 15 that crack 20" (including 5 consecutive...which also included 3 consecutive 40"+ Februarys) and 4 of them producing in excess of 36"...that matches your prolific February period.