"We're gonna need a bigger plow..." Massive, persistent singal now emerges discretely in the models, 20th-23rd

[Great Snow 1717]

20 minutes ago, CT Rain said:

Biggest issue is when stations measure only at 12z and you had a snow to rain situation the day prior. 

Snow to rain situations certainly impacted snowfall totals more back in the day than now.

[40/70 Benchmark]

25 minutes ago, CoastalWx said:

Yeah some just don’t catch that. I’ve seen that too. 
I was more arguing that the 6hr method imo is the more truthful way to gauge snowfalls.

6 hourly method is total storm snowfall. Just distinguish between snowstorm snowfall and depth. Problem solved. 

It's totally normal to have a 27" depth after a 30" snowfall. Your storm total snowfall is 30" with a 27" depth.

[Brian5671]

13 hours ago, George001 said:

 

The pattern did come (-nao, -epo, +pna), but the analogs didn’t work because the earth is warmer than it used to be. Yes I’m blaming climate change for this, I know I’ll get a lot of shit for it but this type of pattern used to be good until the damn ocean furnaced. Hell, the Atlantic is so warm I’m considering going to the cape and trolling for stripers right now in mid December. I bet I’d catch a massive bass. Oh well, on to January. After this cutter it looks like we will get a thaw for a bit on the long range models. I say bring it on, we need a pattern reset and reload. 

You are probably at least partially right.   The NW Atlantic is well above normal and has been for a couple of years-has to play into it...

[Great Snow 1717]

1 minute ago, Brian5671 said:

You are probably at least partially right.   The NW Atlantic is well above normal and has been for a couple of years-has to play into it...

Agree, far too many people fail to mention it or have not noticed. 

[powderfreak]

9 minutes ago, 40/70 Benchmark said:

6 hourly method is total storm snowfall. Just distinguish between snowstorm snowfall and depth. Problem solved. 

It's totally normal to have a 27" depth after a 30" snowfall. Your storm total snowfall is 30" with a 27" depth.

Yeah I never know why this is much of a discussion. They are two separate things.  One is the amount of snow that falls from the sky, the other is the amount of snow on the ground.

It would be like measuring rainfall via run-off.

[CoastalWx]

36 minutes ago, Great Snow 1717 said:

Agree, far too many people fail to mention it or have not noticed. 

Waters a few degrees cooler won’t help areas south of the coastal front like in this storm. Nor does AN SSTs determine nuances like ridges folding over AK and causing a s/w trough to dip into the Gulf Of Alaska from the east.  Maybe borderline areas near 32 in this storm it may matter, but that’s not the problem in this pattern.

[STILL N OF PIKE]

7 minutes ago, powderfreak said:

Yeah I never know why this is much of a discussion. They are two separate things.  One is the amount of snow that falls from the sky, the other is the amount of snow on the ground.

It would be like measuring rainfall via run-off.

The reason is because Many people still measure the “old way “ (end of storm / stick ruler in ) and the second reason (semi related ) is the discrepancy’s can be much larger than 10% , those who live in places where longer  duration snow storms are commonplace annually AND measure by clearing a snowboard im sure have seen major differences after a 30 hr snowfall (between those Who stick ruler in snow At end ) and their approved methods

 I think many Wx buffs (even here )  still underestimate the potential differences between the two methods in many storms of even decent duration and I think that is a reason why the discussion will carry on .

[Brian5671]

24 minutes ago, Great Snow 1717 said:

Agree, far too many people fail to mention it or have not noticed. 

And using analogs from colder times-say pre 1990-are largely worthless these days...

[Great Snow 1717]

15 minutes ago, Brian5671 said:

And using analogs from colder times-say pre 1990-are largely worthless these days...

Agree...and it is why many analog based forecasts fail.

[CoastalWx]

Analogs give you a sense of the 500mb look. So in that sense they work. 

[Ed, snow and hurricane fan]

Southwest Flow Event code for snow early changing to rain?

[ORH_wxman]

46 minutes ago, CoastalWx said:

Waters a few degrees cooler won’t help areas south of the coastal front like in this storm. Nor does AN SSTs determine nuances like ridges folding over AK and causing a s/w trough to dip into the Gulf Of Alaska from the east.  Maybe borderline areas near 32 in this storm it may matter, but that’s not the problem in this pattern.

Yeah it’s like #19 on a list of 20 things. I think many people want it to be a simplistic explanation like that but wx is way more complicated. We’ve had furnace SSTs before in December and cleaned up. An AK ridge folding over has nothing to do with George’s Bank SST anomalies. 

[mahk_webstah]

Why wouldn’t this upcoming storm, with all of the high pressure to the north, not force a triple point low?  What is missing and what would have to happen to get that evolution?  Thanks

[ORH_wxman]

20 minutes ago, CoastalWx said:

Analogs give you a sense of the 500mb look. So in that sense they work. 

If we didn’t use analogs, we’d be forecasting like voo-doo methods back in the early 20th century. The reason we know a western ridge is good for us is because historical analogs tell us how many large storms we got from western ridges.
 

Are western ridges supposed to no longer good for snowfall because it was colder by 0.7C in 1975 than it is now?
 

You can easily adjust for that too in a long range forecast….”normally I’d go -2 to -4 temperature departures but maybe I’ll go -1 to -3 instead because of underlying warming.”

[ORH_wxman]

55 minutes ago, STILL N OF PIKE said:

The reason is because Many people still measure the “old way “ (end of storm / stick ruler in ) and the second reason (semi related ) is the discrepancy’s can be much larger than 10% , those who live in places where longer  duration snow storms are commonplace annually AND measure by clearing a snowboard im sure have seen major differences after a 30 hr snowfall (between those Who stick ruler in snow At end ) and their approved methods

 I think many Wx buffs (even here )  still underestimate the potential differences between the two methods in many storms of even decent duration and I think that is a reason why the discussion will carry on .

A 30 hour snowfall will need to have a minimum of 2 measurements even if you are doing it the lazy way. You must measure at least once in a 24 hour period. 30 hour snowfalls aren’t that common anyway unless you live in upslope land. 

[CoastalWx]

5 minutes ago, ORH_wxman said:

If we didn’t use analogs, we’d be forecasting like voo-doo methods back in the early 20th century. The reason we know a western ridge is good for us is because historical analogs tell us how many large storms we got from western ridges.
 

Are western ridges supposed to no longer good for snowfall because it was colder by 0.7C in 1975 than it is now?
 

You can easily adjust for that too in a long range forecast….”normally I’d go -2 to -4 temperature departures but maybe I’ll go -1 to -3 instead because of underlying warming.”

Yeah exactly. You get a sense of the overall look. An EPO ridge in 1955 and an EPO ridge in 2022 mean the same. Big cold into the CONUS. Maybe adjust by 1F as you said.

[CoastalWx]

10 minutes ago, mahk_webstah said:

Why wouldn’t this upcoming storm, with all of the high pressure to the north, not force a triple point low?  What is missing and what would have to happen to get that evolution?  Thanks

There may be some more HP trying to hold in NNE as we get closer, but as it stands now….the Midwest s/w just overwhelms it. It’s a beast of a low intensifying to our west. 
 

You’d want to see the s/w weaken, have it come in further east from the Rockies compared to where it’s modeled now, or keep better confluence to our north. 

[SnowGoose69]

8 minutes ago, ORH_wxman said:

If we didn’t use analogs, we’d be forecasting like voo-doo methods back in the early 20th century. The reason we know a western ridge is good for us is because historical analogs tell us how many large storms we got from western ridges.
 

Are western ridges supposed to no longer good for snowfall because it was colder by 0.7C in 1975 than it is now?
 

You can easily adjust for that too in a long range forecast….”normally I’d go -2 to -4 temperature departures but maybe I’ll go -1 to -3 instead because of underlying warming.”

The ridge IMO was just too far west...we have had big snows from ridges on or off the W Coast but more often later in winter, with a broad/elongated PV that extends from MB to QC, or with the whole pattern breaking down or about to break down and the ridge progressing east with time...I noted both 1/7/96 and 2/16/03 as cases where the ridge was too far west as the pieces began coming together but the Pac was in the process of being about to blast the nation so the whole pattern was shifting east with time and by the time the phasing was beginning the ridge was over the rockies

[mahk_webstah]

1 minute ago, CoastalWx said:

There may be some more HP trying to hold in NNE as we get closer, but as it stands now….the Midwest s/w just overwhelms it. It’s a beast of a low intensifying to our west. 
 

You’d want to see the s/w weaken, have it come in further east from the Rockies compared to where it’s modeled now, or keep better confluence to our north. 

Thank you for that, very understandable.  It is clear what we want to trend to get something more like a swfe.  The cold before isn’t too bad

[Typhoon Tip]

2 hours ago, Brian5671 said:

And using analogs from colder times-say pre 1990-are largely worthless these days...

Too black or white ...   Scientific wisdom says this is a much too stringent perspective.   Particularly ...the use of that word, "worthless" -

It would only be that way if the undergirding of climate system was excessively different - which it is not.   This is not Venus ... despite the entire state of the climate change zeitgeist. 

The zeitgeist is what it is, because unfortunately .. .humanity does little based upon verbal warning. They have to be struck by discomfort, failing that, fear, to engine motivation to change.  

I've often mused, 'humanity sets upon the proverbial rail tracks, and as the iron beneath their feet has begun to whir ... they don't move off the track - they argue about the style of shoes they wear to the engagement.' 

That's because it is an evolutionary trap ( perhaps, irony...) that we do not really respond to threats unless they directly appeal to the standard senses:  sight, sound, taste, touch, or smell.  If you warn someone of impending doom... they look up and try to observe its truth, utilizing these senses.  But, if they look up and see the impending intersect with the "train" as an observable destiny... they will go great strides to avoid said intersect.  

Climate change is in that folly of evolutionary space.  It doesn't have any advocates that directly expose, thus appeal to these standard senses - although ... indirectly? Sure, as we are seeing evidences in the system that CC's slow cook is a destructive influence now. It is thus no wonder why there are more obvious movements and legislation, in general, around the 'responsible' governments of the world. It's because even so much as an indirect observation framework ... begins to appeal to a sense of realism.   As an aside, ... human ingenuity has outpaced the biological method for downloading information about the surrounding environment.  These "senses" ?  They are nature's "USB ports"

The way to compensate for the "toad in pan of water," unwitting experiment humanity is turned up the heat on itself ( if one is less aware of that cruel experiment, this metaphor won't work...), is to use fear.   It's an unfortunate circumstance that CC has to be over-sold in order to motivate change...  An overselling that leads to people applying CC to every thunderstorm.  Including ...odd patterns of behavior that failed an analog.  Analogs failed in 1980, too.   

The dial on the Global temperature has moved between .85 and 1 deg C, in the last 100 years.  It's not an all or nothing... The cliche, 'shades of gray' is unfortunately apropos.    

 

[ORH_wxman]

RGEM looks like its reverting back to parakeets if extrapolated. So we prob aren’t going to see the GGEM come east against like 00z did. 
 

OTOH, the Icon looks more interesting. Def more confluence up north this run but it’s still not quite enough. 

[Brian5671]

17 minutes ago, ORH_wxman said:

If we didn’t use analogs, we’d be forecasting like voo-doo methods back in the early 20th century. The reason we know a western ridge is good for us is because historical analogs tell us how many large storms we got from western ridges.
 

Are western ridges supposed to no longer good for snowfall because it was colder by 0.7C in 1975 than it is now?
 

You can easily adjust for that too in a long range forecast….”normally I’d go -2 to -4 temperature departures but maybe I’ll go -1 to -3 instead because of underlying warming.”

Fair point but I've seen some patterns where a certain set of analogs are used and then the sensible weather ends up nothing like it...maybe that's just part of the equation it's not always a match in the end...

[mahk_webstah]

7 minutes ago, ORH_wxman said:

RGEM looks like its reverting back to parakeets if extrapolated. So we prob aren’t going to see the GGEM come east against like 00z did. 
 

OTOH, the Icon looks more interesting. Def more confluence up north this run but it’s still not quite enough. 

What creates more confluence; in other words what can we track in short term modeling?

[UnitedWx]

2 minutes ago, mahk_webstah said:

What creates more confluence; in other words what can we track in short term modeling?

I was just wondering the same thing.  It's interesting looking at some of the options runs. They look like they want to spawn a secondary offshore, but then it ends up in upstate NY

[ORH_wxman]

Just now, Brian5671 said:

Fair point but I've seen some patterns where a certain set of analogs are used and then the sensible weather ends up nothing like it...maybe that's just part of the equation it's not always a match in the end...

Analogs are really to be used as probabilistic tools. I know most people just have their eyes glaze over at that term but it’s unfortunately the reality of long range forecasting. Check Jan 1969 and Feb 1969. The patterns aren’t all THAT different but the snowfall and sensible wx was extremely different….and those were one month apart…nevermind years or decades. 
 

Think of it I’m these terms:

1. pattern is really good…so we have a 40% chance of a decent snow event in the next 7-10 days

2. pattern is kind of mediocre/average. We have a 25% chance of a decent snow event in the next 7-10 days

3. pattern sucks donkey balls. We have prob a 10% chance at a decent snow event over the next 7-10 days. 
 

There are no guarantees in any of those statements. But you’d much rather have the higher percentage pattern. But if two shortwaves don’t phase properly or there’s a random over-phase and we get a cutter, then it still won’t work out. Doesn’t really change anything empirical about the longwave pattern either. 

[ORH_wxman]

3 minutes ago, mahk_webstah said:

What creates more confluence; in other words what can we track in short term modeling?

Watch this feature (TPV)…we want it as Far East or southeast as possible…right now it kind of stalls in Ontario and then lifts back north and north west and allows the shortwave behind it to cut up to our west

 

 

[Ginx snewx]

15 minutes ago, ORH_wxman said:

Watch this feature (TPV)…we want it as Far East or southeast as possible…right now it kind of stalls in Ontario and then lifts back north and north west and allows the shortwave behind it to cut up to our west

 

 

I think the subtle but significant orientation of the 250 mb jet is driving this bus. If you look at the Thurs run when models were showing a potential blizzard the jet on the west coast was more broad and less wind. This made cyclogenesis more likely on the East Coast. Now with today 6Z EPS run you can see the speed had greatly magnified in speed and orientation. This created a monster spin inside which forces any secondary inside the coast. The  50 50 low is booted, high pressure is overwhelmed and we are left with a soueaster 

[SouthCoastMA]

maybe some Cape OE snow showers on WSW flow on Christmas Eve for the 2 people who care

[CoastalWx]

The opposite of what you want to see on the gfs.

 

[Ginx snewx]

So as Will and other have pointed out, it's not NAtlantic sea temps or any weird unusual forces created by climate change, its small nuances.