December 2025 OBS and Discussion

[bluewave]

Just now, NittanyWx said:

You're making a lot of assumptions about how I do things and those assumptions are wrong.  I used SAI as an sample of a 'near term' trend with a strong statistical correlation that showed forecastable value off a short sample size and ultimately failed as your sample size got larger.  My correlation work ignores what happens before 1991.  The correlation still fails to reach statistical significant when testing between ENSO, the SOI and any number of corresponding variables when you benchmark them to regional snowfall observations.  

 

You're speaking to someone who has done this professionally in the commodities space for 15 years.  My methodologies discount severely anything before 1991.

We are taking about local and not regional snowfall observations. A broad brush approach doesn’t  always work especially with the wide variation between the coastal plain to mountains areas to the north and west. You need to more narrowly focus the data for the sensible weather from EWR to NYC and LGA for which the relationship is valid. 

[NittanyWx]

1 minute ago, bluewave said:

We are taking about local and not regional snowfall observations. A broad brush approach doesn’t  always work especially with the wide variation between the coastal plain to mountains areas to the north and west. You need to more narrowly focus the data for the sensible weather from EWR to NYC and LGA for which the relationship is valid. 

Those three stations are what I'm testing.  Again, assumption made that is incorrect.  Take an average of those three stations, that's your 'snowfall index'.  Bench that snowfall index to ENSO past 30 years and you get a correlation that fails.

 

So other than arbitrarily fitting it to the data, why does 4" mean something meteorologically?

[bluewave]

5 minutes ago, NittanyWx said:

Those three stations are what I'm testing.  Again, assumption made that is incorrect.

Then your methodology is off. 

[NittanyWx]

4 minutes ago, bluewave said:

Then your methodology is off. 

The math does not hold man, I'm literally sitting here doing the testing and its an overfit.  My best guess is found a value you think makes sense based on recent record and picked it because it fit observed data.  All I've asked you, repeatedly I might add, is why 4" means something statistically and meteorologically.  Why did you choose 4"?   

 

ENSO is not and never really has been a great predictor of snowfall here. 

[bluewave]

6 minutes ago, NittanyWx said:

The math does not hold man, I'm literally sitting here doing the testing and its an overfit.  My best guess is found a value you think makes sense based on recent record and picked it because it fit observed data.  All I've asked you, repeatedly I might add, is why 4" means something statistically and meteorologically. 

 

ENSO is not and never really has been a great predictor of snowfall here. 

Again. You don’t  know what you are talking about if you continue to make these broad assumptions that don’t match our snowfall patterns and relationships. I have seen some of the incomplete work from a number  of the commodity and hedge fund shops which try to pass them off as something meaningful to impress the traders with.

[NittanyWx]

2 minutes ago, bluewave said:

Again. You don’t  know what you are talking about if you continue to make these broad assumptions that don’t match our snowfall patterns. If have seen some of the sloppy work from a number  of the commodity and hedge fund shops which try to pass them off as something meaningful to impress the traders with.

Nice, so now you're calling my work sloppy because you can't find a meteorological reason for why your threshold makes sense other than it 'fits the data'.  You've dodged the question 5 times now.  I know what I am doing and your arrogance is really starting to show here.

 

You haven't seen my work, I can promise you that.  I don't work at a vendor.

[bluewave]

5 minutes ago, NittanyWx said:

Nice, so now you're calling my work sloppy because you can't find a meteorological reason for why your threshold makes sense other than it 'fits the data'.  You've dodged the question 5 times now.

 

You haven't seen my work, I can promise you that.  I don't work at a vendor.

All I know about you is you occasional posts in here mostly early in the winter making bold claims and then you do not come back when they don’t work out.

[NittanyWx]

6 minutes ago, bluewave said:

All I know about you is you occasional posts in here mostly early in the winter making bold claims and then you do not come back when they don’t  work out. 

Posted through the entirety of last winter and had a very good one forecasting wise.  

 

Had a very good one the year prior too.

[SACRUS]

 

27 / 11 clear.   Cold the next 96 hours - coldest Sun evening to Tuesday overnight.  Overnight Saturday into Sunday snow squall/showers bring widespread light snowfall Coasting - 2 inches , 3 in some local spots to the south and east.   Moderation to and above normal as ridge builds from the MO valley east between the 18th and Christmas.  Beyond there closer to normal overall with back and forth shots of cold briefly then warming up.  White Christmas looks in jeopardy, perhaps timed right for New Years eve ala Dec 30 2000?

 

[bluewave]

3 minutes ago, NittanyWx said:

Posted through the entirety of last winter and had a very good one forecasting wise.

 

Had a very good one the year prior too.

You seem to dip into these threads to try to stir up controversy and add snarky comments rather than add to value to the ongoing discussions. 

[NittanyWx]

1 minute ago, bluewave said:

You seem to dip into these threads to try to stir up controversy rather than add to value to the ongoing discussions. 

Asking you about your methodologies and whether they actually make sense meteorologically or whether it's an overfitting of observational data is stirring up controversy now?

[SACRUS]

Records:

Highs:

EWR: 68 (1931)
NYC: 68 (1931)
LGA: 66 (2015)
JFK: 64 (2015)


Lows:

EWR: 6 (1988)
NYC: 5 (1988)
LGA: 8 (1988)
JFK: 7 (1988)

 

Historical:

 

1882 - Portland, OR, was drenched with 7.66 inches of rain, a record 24 hour total for that location. (12th-13th) (The Weather Channel)


1917: Dec. 12-13, Richmond had 8.0 inches on the 12th followed by 1.4 inches on the 13th and 1.0 inches on the 14th for a total of 10.4 inches of snow. The snow cover from this storm lasted for more than a week an after another, smaller snowstorm near Christmas, temperatures plunged to the lowest levels ever recorded in December. On Dec. 30, Richmond woke up to a low of -2°F.

1960 - The first of three Middle Atlantic snowstorms produced a foot of snow at Baltimore MD. A pre-winter blizzard struck the northeastern U.S. producing wind gusts as high as 51 mph, along with 16 inches of snow at Nantucket MA, and 20 inches at Newark NJ. (David Ludlum)

1960: On December 12th 13.0 inches of snow fell over the Boston, Massachusetts area. (Ref. NOAA Boston Weather Events)
Washington, DC. received 8.5 inches of snow from this storm.(Ref. Wilson Wx. Additional information)

1967: December 12th - 20th Flagstaff, Arizona: A series of snow storms buries Flagstaff with 86.0 inches of snow.(Ref. WxDoctor)

1967: New Mexico was bombarded by 11 days of heavy snow beginning on this date. Food had to be airlifted in to some areas. The Reservations of the Native Americans were especially hard hit. Flagstaff, AZ was buried under 86 inches of snow. (Ref. AccWeather Weather History)

1969 - The worst tornado of record for western Washington State tracked south of Seattle, traveling five miles, from Des Moines to Kent. The tornado, 50 to 200 yards in width, began as a waterspout over Puget Sound. One person was injured and the tornado caused half a million dollars damage. (The Weather Channel)

1982: 6.6 inches of snowfall was greatest single December snowfall since 1973. The New England Patriots defeated the Miami Dolphins in driving snow at Foxboro, MA. With snow covering the field and New England in position to kick a game winning field goal, New England Head Coach Ron Meyer ordered the path to be cleared for the field goal attempt. The move was against the rules, but no one stopped him. Place kicker John Smith made the kick and the Patriots won the game 3-0. (Ref. Wilson Wx. History)

1987 - While a developing winter storm began to spread snow across New Mexico into Colorado, high winds ushered unseasonably cold air into the southwestern states. Winds in California gusted to 60 mph in the Sacramento River Delta, and in the San Bernardino Valley. (The National Weather Summary)

1988 - Cold arctic air spread from the Great Lakes Region to the Appalachian Region. Twenty-five cities, mostly in the northeastern U.S., reported record low temperatures for the date. The low of 12 degrees below zero at Albany NY was their coldest reading of record for so early in the season. Saranac Lake NY was the cold spot in the nation with a low of 28 degrees below zero. (The National Weather Summary)

1989 - A winter storm produced snow from northern Mississippi to the Middle Atlantic Coast, with 10.5 inches reported at Powhatan VA. Heavy snow whitened the Black Hills of South Dakota, with 36 inches reported at Deer Mountain. Thirteen cities in the north central U.S., from Minnesota to Texas, reported record low temperatures for the date, including Duluth MN and Yankton SD with morning lows of 22 degrees below zero. (The National Weather Summary) (Storm Data)

1995 - A severe coastal storm is blamed for five deaths and loss of power to over one million people in Oregon and Washington. Winds at Sea Lion Caves near Florence topped out at 119 mph before problems developed with the anemometer. In Newport, a gust of 107 mph occurred downtown, while Astoria and Cape Blanco also had gusts of over 100 mph. Astoria's air pressure dropped as low as 28.53 inches, an all-time record (and comparable to the central pressure of a Category 2 hurricane!). Gusts in the Willamette Valley exceeded 60 mph.

1995: An intense ocean storm at 28.11 inches of mercury battered the West Coast. In Oregon, wind gusts hit 119 mph at Florence, 112 mph at Cannon Beach and 107 mph at Newport. Northern and central California was hit very hard. Wind gusts reached 103 mph at Angel Island, 85 mph at Redding and 74 mph at San Francisco. Three people were killed by falling trees. The San Francisco Conservatory sustained $10 million dollars in damages due to structural failure, broken windows and destroyed plants. Three Peaks was deluged with 21.22 inches of rain. Other heavy totals included 12.27 inches at the Marin Civic Center, 10.64 inches at Blue Canyon and 5.01 inches at San Francisco. Oakland was soaked with 2.66 inches in just 45 minutes. Nearly 2 million people were without power at one time. Seattle, WA and Astoria, OR recorded their lowest pressures on record with 970.2 (28.65 inches of mercury) and 966.1 millibars (28.53 inches of mercury) respectively. This storm was the worst to strike the region in 16 years. Six people lost their lives. (Ref. AccWeather Weather History)
A 5-day lake effect snowstorm came to an end at Sault Ste Marie, MI over which time 61.7 inches of snow fell, by far the city's biggest snowstorm on record. 27.8 inches fell in 24 hours on the 9th and 10th establishing their all-time 24 hour snowfall record. The snow depth reached 50 inches at one point, tying the record. The storm brought the monthly total to 82.5 inches, the city's greatest monthly snowfall ever. International Falls, MN set a record low with -39 °F. (Ref. Wilson Wx. History)

2008 - A significant ice storm wreaked havoc across New York and New England on December 12, disrupting electricity and leaving over 1 million homes and businesses without power. New Hampshire alone had as many as 320,000 residents without power, which according to reports it was described as the worst outages in 30 years (Reuters). Four fatalities were reported and parts of Massachusetts, New Hampshire, New York, and Maine declared a state of emergency (BBC News).

[bluewave]

Just now, NittanyWx said:

Asking you about your methodologies and whether they actually make sense is stirring up controversy now?

They have been posted extensively here which is more than I can say about your data. 

[the_other_guy]

35 minutes ago, NittanyWx said:

You're making a lot of assumptions about how I do things and those assumptions are wrong.  I used SAI as an sample of a 'near term' trend with a strong statistical correlation that showed forecastable value off a short sample size and ultimately failed as your sample size got larger.  My correlation work largely ignores what happens before 1991.  The correlation still fails to reach statistical significant when testing between ENSO, the SOI and any number of corresponding variables when you benchmark them to regional snowfall observations.  

 

You're speaking with someone who has done this professionally in the commodities space for 15 years.  My methodologies discount severely anything before 1991 because it is a different climate regime.  This is an industry that benchmarks to the 10 year normal and not 30 -myself included- so I don't need a lecture and explanation about understanding what regime we are in.  This isn't a discussion about that, it's a discussion about overfitting to an arbitrary value.

 

For the record, I also do detrended analysis to find statistical signals around warmer background trends.  I am very cognizant of the CC forcing arguments you've made and how deeply you believe them.   But as we got into an argument last year about Feb, we're getting into an argument here on what constitues actual statistical signal and more importantly *why* you used a threshold value other than fitting it to observational data.

 

You still need to find a robust statistical *and* meteorological reason for 4" of snow meaning something for us to take any real stock in using it as a metric.  I can test it, I can say 'hey, that's kinda interesting' but you're not giving me a real meteorological reason for why 4" is an actual threshold.  

 

The 4 inch threshold is just a historical marker. Much like accumulating snow before the middle of November leads to a BN total snowfall winter.

 

You won’t find a scientific reason for it. It’s an observation on historical data that you can make a casual correlation with.

 

And the casual correlation that a poster like blue wave has made is that in La Niña winters if we don’t get over 4 inches of snow in December you can expect a below normal snowfall winter.

 

Now, if you wanted to dive deeper into that you could say La Niña shoots its load during December and if not much comes from that, that usually is a good indication that January and February arent going to be much better. That’s more scientific because La Niña is frontloaded for the month of December.

 

But the reality is, these are just historical markers and you can choose to dismiss them as you wish. But better to have a flash light for possible clues then go into January blind expecting an equal chance. Historical data says otherwise.

 

[NittanyWx]

Just now, the_other_guy said:

The 4 inch threshold is just a historical marker. Much like accumulating snow before the middle of November leads to a BN total snowfall winter.

 

You won’t find a scientific reason for it. It’s an observation on historical data that you can make a casual correlation with.

 

And the casual correlation that a poster like blue wave has made is that in La Niña winters if we don’t get over 4 inches of snow in December you can expect a below normal snowfall winter.

 

Now, if you wanted to dive deeper into that you could say La Niña shoots its load during December and if not much comes from that, that usually is a good indication that January and February arent going to be much better. That’s more scientific because La Niña is frontloaded for the month of December.

 

But the reality is, these are just historical markers and you can choose to dismiss them as you wish. But better to have a flash light for possible clues then go into January blind expecting an equal chance. Historical data says otherwise.

 

 

 

Yeah so my only point for this is if there's really something here I think we'd see it in actual statistical correlations with ENSO to snowfall.  Whether that be rate of change of ENSO over the winter, a linear or partial correlation between regional observation and ENSO value itself...just something there that's more robust and can give us something to really sink our teeth into and find out what it's telling us and why.

 

I think your points here aren't far from where I'm at too.  But I'm more curious as to thought process above all else to see if there's something testable.

 

[bluewave]

7 minutes ago, NittanyWx said:

 

 

Yeah so my only point for this is if there's really something here I think we'd see it in actual statistical correlations with ENSO to snowfall.  Whether that be rate of change of ENSO over the winter, a linear or partial correlation between regional observation and ENSO value itself...just something there that's more robust and can give us something to really sink our teeth into and find out what it's telling us and why.

 

I think your points here aren't far from where I'm at too.  But I'm more curious as to thought process above all else to see if there's something testable.

 

The data has been widely posted here by myself and other posters. This isn’t some new and controversial revelation. It’s just one of the many new repeating patterns which have become more pronounced as our climate has rapidly warmed. I suspect we are seeing non-linear shifts which make them so persistent.

[NittanyWx]

3 minutes ago, bluewave said:

The data has been widely posted here by myself and other posters. This isn’t some new and controversial revelation. It’s just one of the many new repeating patterns which have become more pronounced as our climate has rapidly warmed. 

You posted a relational inference based on observed data, yes  We're not arguing about that.

[Nibor]

That little band of snow last night packed a punch.

[the_other_guy]

4 minutes ago, bluewave said:

The data has been widely posted here by myself and other posters. This isn’t some new and controversial revelation. It’s just one of the many new repeating patterns which have become more pronounced as our climate has rapidly warmed. 

It hasnt become more pronounced. it is the same historical pattern. More pronounced would be if that threshold changed to 5 inches, or occurred more frequently.

 

Now, assuming we finish Dec with 3 inches of snow this year. And we wrap up with snow in the low to mid 20s, that would be an interesting April discussion…would this have been an AN winter in a different climate? Is that the new AN? 

[bluewave]

11 minutes ago, the_other_guy said:

It hasnt become more pronounced. it is the same historical pattern. More pronounced would be if that threshold changed to 5 inches, or occurred more frequently.

 

Now, assuming we finish Dec with 3 inches of snow this year. And we wrap up with snow in the low to mid 20s, that would be an interesting April discussion…would this have been an AN winter in a different climate? Is that the new AN? 

I was talking about the fact that repeating patterns have become more pronounced as the climate has warmed. While there was a weaker December to seasonal snowfall relationship prior to the 1990s, it has become more pronounced. 

My theory as to why this is that case is that we are seeing the beginnings of non-linear climate shifts. As convective thresholds begin to be crossed in tropical forcing regions with rapidly warming SSTs, it can be like flipping a switch where patterns start locking in  more and become more persistent.

Now the paper below is very technical, but in a tangential way to our discussion it’s the beginning of some new and potentially promising research. 
 

Circus Tents, Convective Thresholds, and the Non-Linear Climate Response to Tropical SSTs

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2022GL101499

 

 

[BxEngine]

If you cant make a point without insulting someone or their job, its time to rethink your argument. Im too goddamn busy to go delete the nonsense and because there are actual good arguments intertwined. But this shit ends, there is no gatekeeping the threads.

[bluewave]

45 minutes ago, NittanyWx said:

You posted a relational inference based on observed data, yes  We're not arguing about that.

Well it sounded like from the tone of your posts that is what you were questioning. Bx Engine is a hard working guy and I don’t want to tie up his valuable time with disputes that didn’t exist then. Unfortunately, sometimes it’s hard to read intentions on an online forum when you aren’t meeting face to face with someone. 

[CentralNJSnowman]

One other point about the "if you don't exceed 4 inches by end of December, it's going to be a below average year" rule of thumb...you're kind of cheating if you use December to predict the full winter (which includes December).  Much more meaningful test of predictive power would be "If you don't exceed 4 inches by the end of December, then the REMAINING portion of the winter would be below average.

Obviously, with Nov+Dec generally not accounting for a very large proportion of the winter's snow, it's not a HUGE problem, but this like a less extreme version of saying "If a hitter is batting below .300 on September 1st, he's unlikely to hit .300"...obviously true, but not much of a prediction of what will happen

[bluewave]

13 minutes ago, CentralNJSnowman said:

One other point about the "if you don't exceed 4 inches by end of December, it's going to be a below average year" rule of thumb...you're kind of cheating if you use December to predict the full winter (which includes December).  Much more meaningful test of predictive power would be "If you don't exceed 4 inches by the end of December, then the REMAINING portion of the winter would be below average.

Obviously, with Nov+Dec generally not accounting for a very large proportion of the winter's snow, it's not a HUGE problem, but this like a less extreme version of saying "If a hitter is batting below .300 on September 1st, he's unlikely to hit .300"...obviously true, but not much of a prediction of what will happen

This is broad-brushing on your part since we are discussing a particular subset of Decembers that are based on La Niña which has  been more recently defined by RONI as the global oceans have rapidly been warming.

La Nina’s historically have been defined by an early start to winter relative to El Niños. This is why you see frequent references to frontloaded and backloaded winters.

So it makes it easier for us to use a December as a marker for the rest of the season due to the nature of La Ninas. 

[CentralNJSnowman]

2 minutes ago, bluewave said:

This is broad-brushing on your part since we are discussing a particular subset of Decembers that are based on La Niña which has  been more recently defined by RONI as the global oceans have rapidly been warming.

La Nina’s historically have been defined by an early start to winter relative to El Niños. This is why you see frequent references to frontloaded and backloaded winters

So it makes it easier for us to use a December as a marker for the rest of the season due to the nature of La Ninas. 

If you're saying "most of the snow in La Nina comes early, so by the end of December a substantial portion of our opportunity has passed" - sure, I agree 100%

But I think a lot of people bring up the rule of thumb as a way of predicting what will happen in Jan+Feb, implying that good Dec means good Jan+Feb and bad Dec means bad Jan+Feb.  That might be true, but you can't analyze it by looking at correlation between Dec and full winter totals

[North and West]

You guys shouldn’t forget to remind the kids that Santa isn’t real.


.

[bluewave]

Just now, CentralNJSnowman said:

If you're saying "most of the snow in La Nina comes early, so by the end of December a substantial portion of our opportunity has passed" - sure, I agree 100%

But I think a lot of people bring up the rule of thumb as a way of predicting what will happen in Jan+Feb, implying that good Dec means good Jan+Feb and bad Dec means bad Jan+Feb.  That might be true, but you can't analyze it by looking at correlation between Dec and full winter totals

The relationship has worked out over 90% of the time for the last 15 La Ninas since the 1990s.

But this doesn’t mean that it’s guaranteed to be a solid 100% for every single La Niña we continue to have.

Just that it can be used a a reliable marker most La Niña years as to whether we can expect above or below average seasonal snowfall based on what happens in December.  

[weatherpruf]

2 hours ago, bluewave said:

You seem to dip into these threads to try to stir up controversy and add snarky comments rather than add to value to the ongoing discussions. 

here's where you can use qualitative data....62 years here, 63 next week....can't tell you much about the 60s, but the 70s were colder, i would see frozen ground in november, we had only one real big event in cnj in the 70s. mid feb 78....snow remained scarce in the 80s except for jan and april 82, feb 83, jan 87, and a freak november event in 89. nada until the harsh winter of 94, one big event in feb 95, the gold standard of 96, nada until dec 2000, then the aughts begin with blockbuster winters in between snow droughts, until around 2015, with a big daddy and 2016, and nothing really big till 2021. 2018 and 2022 were decent south and east, 2024 had a few events. been rather quiet otherwise, and warmth the likes of which someone my age never saw as a child. that is qualitative, observational, and not scientific. however, failing to use qualitative data which was readily available caused scientists to badly underestimate how much overfishing has been taking place; they did not ask anglers, seafood buyers or markets, what they had observed over the decades, relying a lot on trawl data. what you guys are arguing over is esoterica for me, but i can tell you, its warmer and doesn't snow as much lately. now, my next question would be, what does the peer reviewed literature say? this is like the experts on dog evolution, one arguing they all descended from the european wolf, the other saying nonsense, it was clearly some smaller animal.....but i do get a kick out of reading it all.

[weatherpruf]

6 minutes ago, CentralNJSnowman said:

If you're saying "most of the snow in La Nina comes early, so by the end of December a substantial portion of our opportunity has passed" - sure, I agree 100%

But I think a lot of people bring up the rule of thumb as a way of predicting what will happen in Jan+Feb, implying that good Dec means good Jan+Feb and bad Dec means bad Jan+Feb.  That might be true, but you can't analyze it by looking at correlation between Dec and full winter totals

we did have the jan 2016 blockbuster after a warm snowless december, but it was really a one off kinda winter....

[Stormlover74]

Just now, weatherpruf said:

we did have the jan 2016 blockbuster after a warm snowless december, but it was really a one off kinda winter....

Pretty sure that 4" rule only pertains to la nina winters. Many winters that were el ninos have been backloaded with very little before January and still wound up above average