January Storm Term Threat Discussions (Day 3 - Day 7)

[CAPE]

26 minutes ago, Chris78 said:

The TPV on the cmc is further north compared to the Gfs.

The cmc actually trended the TPV  further north compared to it run last night. 

That's really what we need.

 

 

Look where the TPV was on the CMC a few runs ago. It still produced a nice snowstorm for the area.

[Chris78]

2 minutes ago, CAPE said:

Look where the TPV was on the CMC a few runs ago. It still produced a nice snowstorm for the area.

So what needs to happen? Get the NA trough out of the way to allow to our SW to amplify more/earlier?

[CAPE]

Just now, Chris78 said:

So what needs to happen? Get the NA trough out of the way to allow to our SW to amplify more/earlier?

At this juncture, we can point out what we think needs to happen, but not sure any of it is fixable. Probably should root for the TPV to drop the eff in and phase.

[frd]

33 minutes ago, psuhoffman said:

40 minutes ago, osfan24 said:

at all.

The ensembles are only as good as the operational they are based on. They can’t help if the core model is wrong.  Their usefulness is in telling us of the operational had a fluke run and went off on a tangent due to some discreet error even by its own physics.  They offer a scope of variability within the physics of that model. But if the model is wrong about something due to a core bias that flaw will infect the ensembles also.  All the ensembles agreeing with the op said was that the op wasn’t a fluke within its own physics parameters. But ensembles don’t ensure the models physical representations are sound.  You need to compare to other guidance to determine and guess at that. 

The past few winters it appears all the various model ensembles have had major set backs. Statistically speaking I can not prove it, but one could perceive the overall accuracy has declined. If anything,  achieving phasing in a favorable thermal environment is a losing battle the last three years.  Very frustrating for sure. 

[stormtracker]

Now we await the Euro to finish this off and we can go on the hunt for salvaging February.   Which may not be possible?

[cbmclean]

1 minute ago, stormtracker said:

Now we await the Euro to finish this off and we can go on the hunt for salvaging February.   We may not be possible?

That says it all: "We may not be possible"

[stormtracker]

2 minutes ago, cbmclean said:

That says it all: "We may not be possible"

"Which"*

[osfan24]

4 minutes ago, stormtracker said:

Now we await the Euro to finish this off and we can go on the hunt for salvaging February.   We may not be possible?

Yeah, we are probably 24-48 hours away from officially setting our sights on the big President's Day storm.

 

[Dabuckeyes]

Prediction:  Euro shows a slight north tick.  Everyone gets excited and overanalyzes how this may work.  Weather Will shows the same percentage map he has shown the past 3 months. Then we await the HH GFS which pulls the rug.

 

[frd]

Still can't believe the arctic oscillation has been negative since December 1st with several dives down below -2 standard deviations, but  only one event to show for it. Will seasonal wavelengths changes help in February,  hard to tell with the outcomes so far. 

[cbmclean]

Just now, stormtracker said:

"Which"*

I like the original better: "We may not be possible" really expresses the existential crisis that affects snow lovers in the southern half of eastern North America right now.

[cbmclean]

Just now, frd said:

Still can't believe the arctic oscillation has been negative since December 1st with several dives down below -2 standard deviations, but  only one event to show for it. Will seasonal wavelengths changes help in February,  hard to tell with the outcomes so far. 

Cold.  We.  Must.  Have.  Cold.  It is clear that the current seasonal thermal profile is not going to support sufficient dynamics to "make its own cold" for significant snow in the eastern CONUS. 

[psuhoffman]

34 minutes ago, jaydreb said:

So I’m starting to agree with that poster who always pops in to say the models suck.  If an ensemble suite can show that much certainty within 5 days and be wrong then what’s the point of having it at all?

Don’t confuse user error with tool error. That poster has no clue how to use nwp. The purpose of ensembles is to tell us what a reasonable range of variability is according to THAT models physical interpretation.  So they can tell us if a situation is highly volition by spread. Or they can tell us if the op likely had a bad run (even by its own physics). But an ensemble can’t correct for the parent operationals biases and core mistakes because it is a derivative of that model.  You have to look at other guidance.  
 

Furthermore the guidance didn’t fail here. It’s done pretty good. From like 200-360 hours it identified this general setup. And it keyed on a possible event on the mid Atlantic coast. But from that range they cannon accurately predict the discreet details, like a weak wave that lingers and lowers heights some in front of it or a vort cut off under a block meandering around in Canada, that will determine exactly how amplified and exactly where a storm hits. If you’re judging NWP by details on synoptic events at day 7+ then that’s like grading your QB only by his completion rate on 50 yard Hail Mary passes.  
 

As we got within 7 days the preponderance of evidence started to show warts that threatened this event. The gfs showing a snowstorm doesn’t mean “guidance says a snowstorm”. The best guidance we have the euro has been saying hold on for days now.  The second best the UK was never on board. The ggem was the next most amplified but it was further south and its ensembles were even less enthused.  Most of the JV models were south. Taken in totality the evidence suggested the gfs was over amplified. We expected this to happen.  We all knew the gfs all alone was likely to cave.  I had hoped maybe the guidance across the board was dampening the wave coming out of the west too much but the last 24 hours the lack of why move that way in the euro and UK and the slow degradation in the gfs and ggem had me realizing where this was likely headed. Not for sure yet but don’t look good. 
 

  Imo guidance has been incredibly good giving us a good idea how this threat was evolving at a good range if you know how to be unbiased and use them. 

[jaydreb]

Just now, psuhoffman said:

Don’t confuse user error with tool error. That poster has no clue how to use nwp. The purpose of ensembles is to tell us what a reasonable range of variability is according to THAT models physical interpretation.  So they can tell us if a situation is highly volition by spread. Or they can tell us if the op likely had a bad run (even by its own physics). But an ensemble can’t correct for the parent operationals biases and core mistakes because it is a derivative of that model.  You have to look at other guidance.  
 

Furthermore the guidance didn’t fail here. It’s done pretty good. From like 200-360 hours it identified this general setup. And it keyed on a possible event on the mid Atlantic coast. But from that range they cannon accurately predict the discreet details, like a weak wave that lingers and lowers heights some in front of it or a vort cut off under a block meandering around in Canada, that will determine exactly how amplified and exactly where a storm hits. If you’re judging NWP by details on synoptic events at day 7+ then that’s like grading your QB only by his completion rate on 50 yard Hail Mary passes.  
 

As we got within 7 days the preponderance of evidence started to show warts that threatened this event. The gfs showing a snowstorm doesn’t mean “guidance says a snowstorm”. The best guidance we have the euro has been saying hold on for days now.  The second best the UK was never on board. The ggem was the next most amplified but it was further south and its ensembles were even less enthused.  Most of the JV models were south. Taken in totality the evidence suggested the gfs was over amplified. We expected this to happen.  We all knew the gfs all alone was likely to cave.  I had hoped maybe the guidance across the board was dampening the wave coming out of the west too much but the last 24 hours the lack of why move that way in the euro and UK and the slow degradation in the gfs and ggem had me realizing where this was likely headed. Not for sure yet but don’t look good. 
 

  Imo guidance has been incredibly good giving us a good idea how this threat was evolving at a good range of you know how to be unbiased and use them. 

Thanks.  Sounds like guidance as a whole has been good but the GEFS/GFS appears to be terrible.  I guess we kinda knew that. 

[psuhoffman]

25 minutes ago, frd said:

The past few winters it appears all the various model ensembles have had major set backs. Statistically speaking I can not prove it, but one could perceive the overall accuracy has declined. If anything,  achieving phasing in a favorable thermal environment is a losing battle the last three years.  Very frustrating for sure. 

It seems anecdotally that spread has decreased days 5-10 on ensembles on both the gfs and euro. They almost always agree with the op now. That is less helpful Imo. 

[Kevin Reilly]

1 hour ago, Chris78 said:

Cmc is close to a big hit. 

 

We need to get that D#&n lobe in Canada to get the hell out of the way.

Wouldn't it be something if Dr. No Trends north with the TPV up north too like the CMC and all the other modes at 0z tonight adjust everything north it may happen?  

[Dabuckeyes]

It appears the UKIE does not get any precip into MD.  

[MDstorm]

Hopefully things change for the  better.  However,  right now, the return on investment of this 2300 plus response thread reminds me of my Blockbuster Video stock. 

[WEATHER53]

39 minutes ago, jaydreb said:

So I’m starting to agree with that poster who always pops in to say the models suck.  If an ensemble suite can show that much certainty within 5 days and be wrong then what’s the point of having it at all?

You are quite correct

Models exist to  sustain themselves. It’s all we’ve had for 30 years and they are not looking into any different methods. The very nature of ensembles is to further the cover all bases method such that come funding time one of those 30 panels can be presented as confirmation to the unknowing Dept  of Commerce  people.

Im a weather nut  also and let’s face it the cartoons are fun to look at. They are just not predictive of weather but rather illustrative of it 

Not a troll either but rather experientially seasoned. Used to be 100+ of us clamoring about models back in 2005, over time as the blooms faded participants of regularity have shrunk to 20 all of whom vigorously defend their baby.

I thank all of you who helped educate me about 850s and 500 and a Few other things but models and many of the alphabet soup of indexes have not proven to be general fund of knowledge enhancing 

Thank you for the courage of your comment, more of same is needed even with the chastizements  we face 

[Rhino16]

19 minutes ago, psuhoffman said:

Imo guidance has been incredibly good giving us a good idea how this threat was evolving at a good range if you know how to be unbiased and use them. 

Guidance being the key word there right? That’s what it is, a guide...

[SnowDreamer]

5 minutes ago, MDstorm said:

Hopefully things change for the  better.  However,  right now, the return on investment of this 2300 plus response thread reminds me of my Blockbuster Video stock. 

Maybe we can set up a VIX for regional snow sentiment. I’d love to see that. We’ve certainly had an up day in the last 24 hours. 

[PrinceFrederickWx]

35 minutes ago, frd said:

Still can't believe the arctic oscillation has been negative since December 1st with several dives down below -2 standard deviations, but  only one event to show for it. Will seasonal wavelengths changes help in February,  hard to tell with the outcomes so far. 

I often wonder if these indices are actually correlated in the way we think- seems like most of the research on this is derived from comparing prior years’ data with outcomes, which is a relatively small sample size.

[MDstorm]

7 minutes ago, SnowDreamer said:

Maybe we can set up a VIX for regional snow sentiment. I’d love to see that. We’ve certainly had an up day in the last 24 hours. 

VIX would frequently be very high around here.

[Wonderdog]

Why does anyone believe a snowy model run outside five days in the MA?

[coastal front]

Long time lurker new member here and even though I’m from the south Jersey shore this forum is my go to. A lot of times what happens in the dc area has similar sensible weather in my area. With that said I still believe this storm to be close enough and given the high volatility with that tpv that I would not write this storm off yet regardless of today’s model runs. To end my introductory post I want to thank all of you guys for your great analysis ( besides that ji dude)   ; )

[psuhoffman]

14 minutes ago, WEATHER53 said:

You are quite correct

Models exist to  sustain themselves. It’s all we’ve had for 30 years and they are not looking into any different methods. The very nature of ensembles is to further the cover all bases method such that come funding time one of those 30 panels can be presented as confirmation to the unknowing Dept  of Commerce  people.

Im a weather nut  also and let’s face it the cartoons are fun to look at. They are just not predictive of weather but rather illustrative of it 

Not a troll either but rather experientially seasoned. Used to be 100+ of us clamoring about models back in 2005, over time as the blooms faded participants of regularity have shrunk to 20 all of whom vigorously defend their baby.

I thank all of you who helped educate me about 850s and 500 and a Few other things but models and many of the alphabet soup of indexes have not proven to be general fund of knowledge enhancing 

Thank you for the courage of your comment, more of same is needed even with the chastizements  we face 

You would have NO idea there would be a wave anywhere along along the east coast producing a snow threat somewhere between NC and PA Thursday from 10 days away without using NWP. There is no way to extrapolate that far out using old school methods.  It’s a miracle of science we saw this threat along the east coast from day 15!!!  You’re using an example of a success as if it’s a failure!  

[Buddy1987]

Without rubbing salt in the wound here are we out of the woods for wild swings down this way or do you guys feel like it could still trend even more south because of the tpv?

[Ji]

Without rubbing salt in the wound here are we out of the woods for wild swings down this way or do you guys feel like it could still trend even more south because of the tpv?

The Canadian tpv is way north of the gfs but the storm isn't much more north. There are other influences

Sent from my SM-G981V using Tapatalk

[PivotPoint]

I think it’s probably ok for me to say it’s likely this will slide south of us. Two days ago when I said it I was chastised big time but unfortunately my fears have come true. I hate that euro is usually right, ugh

[BTRWx's Thanks Giving]

The euro shows highest snow totals in VA barely reaching 2".