December 2017 Mid-Long Range Disco 2

[eurojosh]

To be fair, the 6z GFS solution at 192 is close to something if not for that GLL, as always. It almost looks like a Miller b transfer in reverse, with energy jumping from the Atlantic to the GL.

[Bob Chill]

I wonder if DT will acknowledge the fact that the 0z eps notably shifted towards the gefs with the ridge/warmth not getting knocked out until after Christmas. 

[BristowWx]

3 minutes ago, Bob Chill said:

I wonder if DT will acknowledge the fact that the 0z eps notably shifted towards the gefs with the ridge/warmth not getting knocked out until after Christmas. 

Or JB?  What tale will he spin?  Or maybe they will be right.  Not likely but not impossible. 

[aldie 22]

6 minutes ago, Bob Chill said:

I wonder if DT will acknowledge the fact that the 0z eps notably shifted towards the gefs with the ridge/warmth not getting knocked out until after Christmas. 

You've made your mind up?

[showmethesnow]

13 minutes ago, Ralph Wiggum said:

Nice writeup. I was looking closely at the EPS mean and seeing some interesting discrepancies, so clearly things are getting skewed around based on some anomalous members. Looking solely at the 25th (since this is a date alot of folks have their eyes on), the mean slp maps show sprawled out HP from British Columbia all the way stretched across the Canadian Border extending into the Plains with the Eastern lobe into SE Canada over towards Nova Scotia. Looking again at the mean surface, still some weakish CAD signals from late on the 24th thru very early Christmas morning BUT the mean shows the CAD fading with the front hung up over the Gulf Stream and at least 2 waves nearby the coast giving precip to the region based on surface and precip means centered on the 25th. Here comes the discrepancies because so for this all looks OK as the front/boundary has cleared us and moved SE. When you look at 2m temps, they are actually AN for that day yet the surface and 500mb maps say CAA should have already occurred and temps should be much colder at the surface than the mean EPS shows.

Imo, this a reflection of the tight gradient setting up between arctic cold and SER influenced 'warmth'. There will clearly be some anomalous AN+ temps nearby right to the S and E of that boundary. The individuals pumping the ridge or being slower with the frontal boundary are skewing surface temps in the mean to the warm side. I think this date and the period in general from Dec 25-Dec 30ish needs to be watched for something coming N along the old frontal boundary. If the scenario played out perfectly there would be a heck of a slug of overunning with the SER forcing precip over the dome of HP settling East. I will gladly accept a weaker coastal boundary wave or twi tho as these have proven to work for parts of the region thus far.

Thank you.

Yeah I have noticed conflicting signals as well. Kind of figured we were seeing quite a bit of disconnect between some of the members which is kind of expected with our current setup. Not to mention the huge temp differences over short distances in combination with minor timing differences can really skew things. So this has basically forced me into mostly focusing on the means in the hopes that they have the right general idea. Otherwise diving deep into the members would just give me a massive headache.

[Ralph Wiggum]

I wonder if DT will acknowledge the fact that the 0z eps notably shifted towards the gefs with the ridge/warmth not getting knocked out until after Christmas. 

So you're saying we're locked in for the 25th with ridge/warmth hanging strong? Or just saying all means show this?

 

[Bob Chill]

11 minutes ago, leesburg 04 said:

You've made your mind up?

Mostly yea, but going definitive this far out is foolish of course. A lot of data is stacking against us for winter wx on the holiday. That needs to start changing fast this week to pull me back in. 

I'm not liking the upper level pattern at all anymore. It has morphed into a look that rarely delivers snow here. What once looked like hp/cad over the top now looks like cold chasing precip. 

Beyond Christmas looks like big cold is coming to much of the conus to that's good. Still not a fan of the upper level pattern in general. Has the look of big dry cold with precip chasing on the exit. That's way the F out there though. We can discuss how the cold works for us once it gets here in a week or so. I'm focused on the holiday snow chances and from where I sit it ain't lookin good

 

[cae]

9 hours ago, Cobalt said:

Much weaker signal for the SE ridge's extent on the 0z GEFS. Again, I can't post since I can't post image files larger than 0.03MB

Have you tried imgur.com?  It's free and with unlimited storage, so you don't need to delete old images (which, I believe, then disappear from old posts).  It takes about 10 seconds to upload an image and add it to your post.

[PhineasC]

Just now, Bob Chill said:

Mostly yea, but going definitive this far out is foolish of course. A lot of data is stacking against us for winter wx on the holiday. That needs to start changing fast this week to pull me back in. 

I'm not liking the upper level pattern at all anymore. It has morphed into a look that rarely delivers snow here. What once looked like hp/cad over the top now looks like cold chasing precip. 

Beyond Christmas looks like big cold is coming to much of the conus to that's good. Still not a fan of the upper level pattern in general. Has the look of big dry cold with precip chasing on the exit. That's way the F out there though. We can discuss how the cold works for us once it gets here in a week or so. I'm focused on the holiday snow chances and from where I sit it ain't lookin good

 

I think you are chasing snow on Christmas whereas most others are chasing 45 degrees. Might be some different expectations here. 

[Ralph Wiggum]

Mostly yea, but going definitive this far out is foolish of course. A lot of data is stacking against us for winter wx on the holiday. That needs to start changing fast this week to pull me back in. 
I'm not liking the upper level pattern at all anymore. It has morphed into a look that rarely delivers snow here. What once looked like hp/cad over the top now looks like cold chasing precip. 
Beyond Christmas looks like big cold is coming to much of the conus to that's good. Still not a fan of the upper level pattern in general. Has the look of big dry cold with precip chasing on the exit. That's way the F out there though. We can discuss how the cold works for us once it gets here in a week or so. I'm focused on the holiday snow chances and from where I sit it ain't lookin good
 

I can agree somewhat with what u r saying irt the holiday. It still seems there is a fair amount of disagreement and that is ALOT of energy floating around out West which will have huge implications downstream pending interactions, timing, etc. We are probably walking a fine line and if it hasnt been for the breaks we've had to the good side this season, I would be more in line to just chalk it up as a loss. I know this is a different setup, but I still feel there are good possibilities abound even given some of the trending. Still 8 days out.

[SnowGoose69]

5 minutes ago, Bob Chill said:

Mostly yea, but going definitive this far out is foolish of course. A lot of data is stacking against us for winter wx on the holiday. That needs to start changing fast this week to pull me back in. 

I'm not liking the upper level pattern at all anymore. It has morphed into a look that rarely delivers snow here. What once looked like hp/cad over the top now looks like cold chasing precip. 

Beyond Christmas looks like big cold is coming to much of the conus to that's good. Still not a fan of the upper level pattern in general. Has the look of big dry cold with precip chasing on the exit. That's way the F out there though. We can discuss how the cold works for us once it gets here in a week or so. I'm focused on the holiday snow chances and from where I sit it ain't lookin good

 

The GFS also has some ensembles that by Day 14-15 want to pump the SE ridge again.  Too far out to take seriously but it does look like it tries coming right back on some members 

[Bob Chill]

1 minute ago, PhineasC said:

I think you are chasing snow on Christmas whereas most others are chasing 45 degrees. Might be some different expectations here. 

Probably. We're usually shut out of snow chances by now so it's still interesting at least so there's that. What sort of temps we have on Christmas is really hard to say.  40's could come easy. So could 50s and 60s. My guess is 30's won't be as easy but would love to be proven wrong. 

[Ralph Wiggum]

The GFS also has some ensembles that by Day 14-15 want to pump the SE ridge again.  Too far out to take seriously but it does look like it tries coming right back on some members 

That feature is not going to disappear this season imo. Back in 95-96 Nina the fluxes of the SER helped provide frequent chances, just as an example. Its when it locks into position for weeks at a time with little to no ebb/flow we can get stuck in a rut. As long as we can establish a pattern where there is transition between SER fluxes, that is when we will score our chances. Now if we could just get a fricken -NAO to pop without being a one day transient feature.

[Bob Chill]

1 minute ago, Ralph Wiggum said:

7 minutes ago, Bob Chill said:

Mostly yea, but going definitive this far out is foolish of course. A lot of data is stacking against us for winter wx on the holiday. That needs to start changing fast this week to pull me back in. 
I'm not liking the upper level pattern at all anymore. It has morphed into a look that rarely delivers snow here. What once looked like hp/cad over the top now looks like cold chasing precip. 
Beyond Christmas looks like big cold is coming to much of the conus to that's good. Still not a fan of the upper level pattern in general. Has the look of big dry cold with precip chasing on the exit. That's way the F out there though. We can discuss how the cold works for us once it gets here in a week or so. I'm focused on the holiday snow chances and from where I sit it ain't lookin good
 

I can agree somewhat with what u r saying irt the holiday. It still seems there is a fair amount of disagreement and that is ALOT of energy floating around out West which will have huge implications downstream pending interactions, timing, etc. We are probably walking a fine line and if it hasnt been for the breaks we've had to the good side this season, I would be more in line to just chalk it up as a loss. I know this is a different setup, but I still feel there are good possibilities abound even given some of the trending. Still 8 days out.

I don't disagree with you. There's a lot going on. However, if you showed me just the ens mean h5 panels for the 24th/25th and asked what I thought the first thing I would say is I doesn't look like a good snow pattern at all. If it snows it's a thread the needle pure luck setup with the glaring issue being AN to much AN temps leading in. All models agree on cold chasing precip now. While there's still a good bit of time and yes there's a chance, the chance is not looking good. 

[aldie 22]

Hey Bob, always appreciate your thoughts. 

[Ralph Wiggum]

Hey Bob, always appreciate your thoughts. 

Strongly agree.

[showmethesnow]

1 hour ago, BristowWx said:

Another great write up Showme....perfect read for morning coffee.  6z did look rather uneventful once the front passes.  Still far out but a dry cold look for sure after 25th.  Still it avoids all out torch that run. Best we can hope for perhaps.  

 

1 hour ago, RDM said:

Another excellent write-up showme...  Your balance of technical depth presented in plain ole English is a benchmark to shoot for.  Not sure what you do daily for a living, but you've clearly honed some impressive presentation skills.  Well done...

As a cursed engineer, I try to visualize the fluid dynamics of what's going on in the atmosphere.  That said, visualizing it is one thing, being able to eloquently present it is another.  And, you've done that with aplomb. 

Am hoping the more progressive influx of the PV keeps the WAR far enough off the coast to keep us on the colder side of the boundary.  Would be great to see several waves come through and give us a nice ride into 18. 

Thank you both.

Quick aside: Are others having issues with posts showing up, not showing up with these new boards?

Bristow,

Still not sure what to expect for Christmas. The timing at this point is so close as to whether cold can get in let alone if we actually have a storm it is anyone's guess. I would not be surprised that we really see no resolution until later in the week when the models actually can get a handle on what happens in regards to the SW trough. 

RDM,

When I first started following weatherboards nothing was more discouraging then having all the technical jargon thrown at me. Spent so much time trying to figure out what they were saying that much of the enjoyment was lost. Another thing that was frustrating was quite often ideas were thrown out that went from step A immediately to Step F with the stepping stones (B, C, D, E) between left out under the assumption that you already knew the process. So I have tried my best to keep the terms simple where even a new person can get the general jist of what I am talking about (besides big words hurt my head ). I have also tried to give detailed steps/diagrams to how we are going from A to F for those do not understand the process. So I appreciate your comment because maybe it means I am succeeding in getting my thoughts across.

[EastCoast NPZ]

7 minutes ago, Ralph Wiggum said:

11 minutes ago, SnowGoose69 said:

The GFS also has some ensembles that by Day 14-15 want to pump the SE ridge again.  Too far out to take seriously but it does look like it tries coming right back on some members 

That feature is not going to disappear this season imo. Back in 95-96 Nina the fluxes of the SER helped provide frequent chances, just as an example. Its when it locks into position for weeks at a time with little to no ebb/flow we can get stuck in a rut. As long as we can establish a pattern where there is transition between SER fluxes, that is when we will score our chances. Now if we could just get a fricken -NAO to pop without being a one day transient feature.

A -NAO is every bit as real as Santa Claus.

[Ralph Wiggum]

NAM keeps ticking the midweek system Northward fwiw. Not sure if this keeps ticking we move the boundary and cold air N as well or if nosing HP would allow for overunning to happen. Probably nothing but we've seen a few times already where things worked in our favor. More for this particular region to keep an eye on anyway rather than my home region where we are probably too far N pending any unforseen major shifts. Just something to watch anyway.

[RDM]

3 minutes ago, showmethesnow said:

 

Thank you both.

Quick aside: Are others having issues with posts showing up, not showing up with these new boards?

Bristow,

Still not sure what to expect for Christmas. The timing at this point is so close as to whether cold can get in let alone if we actually have a storm it is anyone's guess. I would not be surprised that we really see no resolution until later in the week when the models actually can get a handle on what happens in regards to the SW trough. 

RDM,

When I first started following weatherboards nothing was more discouraging then having all the technical jargon thrown at me. Spent so much time trying to figure out what they were saying that much of the enjoyment was lost. Another thing that was frustrating was quite often ideas were thrown out that went from step A immediately to Step F with the stepping stones (B, C, D, E) between left out under the assumption that you already knew the process. So I have tried my best to keep the terms simple where even a new person can get the general jist of what I am talking about (besides big words hurt my head ). I have also tried to give detailed steps/diagrams to how we are going from A to F for those do not understand the process. So I appreciate your comment because maybe it means I am succeeding in getting my thoughts across.

Yes, yes and yes.   Yes, there appears to be some remaining quirks since the upgrade.  Yes, re the logical way you delineate your thoughts and yes, re your success in getting your prognosis out in a discernible context that even a weenie wannabe like me can contemplate.

[Scarlet Pimpernel]

24 minutes ago, Bob Chill said:

Mostly yea, but going definitive this far out is foolish of course. A lot of data is stacking against us for winter wx on the holiday. That needs to start changing fast this week to pull me back in. 

I'm not liking the upper level pattern at all anymore. It has morphed into a look that rarely delivers snow here. What once looked like hp/cad over the top now looks like cold chasing precip. 

Beyond Christmas looks like big cold is coming to much of the conus to that's good. Still not a fan of the upper level pattern in general. Has the look of big dry cold with precip chasing on the exit. That's way the F out there though. We can discuss how the cold works for us once it gets here in a week or so. I'm focused on the holiday snow chances and from where I sit it ain't lookin good

 

I'm 50/50 on any potential Holiday event interest, myself.  It would be great, of course, if we could get something wintry on Christmas.  But I don't much like the indications in the overall pattern right now for that, either.  Whether it's very warm or cold, I just hope it's at least a nice day out (heavy snow would count as a nice day of course!)...rainy and any temperature would be kind of a drag.

The week between Christmas and New Year's perhaps might have more to offer us, but that is getting a bit out in time.  Seems that was perhaps the better possibility anyhow for some time.  I'd take something fun to track then, even if it meant "giving up" snow for Christmas.

[Bob Chill]

14 minutes ago, leesburg 04 said:

Hey Bob, always appreciate your thoughts. 

There have been many times in recent years where I wish I could turn the clock back to 2006 when I didn't use ensembles, understand upper air plots, and basically had blind hope 24/7. 

[Scarlet Pimpernel]

15 minutes ago, EastCoast NPZ said:

A -NAO is every bit as real as Santa Claus.

Ha!!  That does seem true the past few years!!

 

[AfewUniversesBelowNormal]

Maybe in a few days it snows. Abundant moisture seems to hit a wall on the NAM

[WhiteoutWX]

1 hour ago, Bob Chill said:

Mostly yea, but going definitive this far out is foolish of course. A lot of data is stacking against us for winter wx on the holiday. That needs to start changing fast this week to pull me back in. 

I'm not liking the upper level pattern at all anymore. It has morphed into a look that rarely delivers snow here. What once looked like hp/cad over the top now looks like cold chasing precip. 

Beyond Christmas looks like big cold is coming to much of the conus to that's good. Still not a fan of the upper level pattern in general. Has the look of big dry cold with precip chasing on the exit. That's way the F out there though. We can discuss how the cold works for us once it gets here in a week or so. I'm focused on the holiday snow chances and from where I sit it ain't lookin good

 

This basically sums up my thoughts as well. The pattern has managed to morph from an extended overrunning threat with multiple chances to a much more amplified pattern which may be good for delivering cold, especially to the center of the country, but without blocking that SE ridge will likely keep everything too far north or west. A shame really, I love overrunning scenarios. Like you said, this looks mostly like warm then cold and dry. 

[showmethesnow]

24 minutes ago, Bob Chill said:

There have been many times in recent years where I wish I could turn the clock back to 2006 when I didn't use ensembles, understand upper air plots, and basically had blind hope 24/7. 

Sometimes I wonder this as well. But I don't think my heart could handle the emotional roller coaster of those by gone weenie days. The days of continually hitting refresh for the following hour on the op all the while hoping that the storm would move north/south/east/west on the next frame. Seeing that fantasy storm in the long range and thinking in your mind that it was a done deal only to have a Met go 'Fools gold'. Or seeing nothing and being downcast only to have a Met tell you "Nah, there should be something there'. And this is just the emotional storm during the run itself. Try waiting 6/12 hours with your emotions at an all time high because it had a 2' blizzard on the previous run only to have nothing show up on the new run. From the heights of heaven to the pits of he!! your emotions fall, just in a matter of minutes.

Nah, I think I prefer the way it is now with an understanding of what's involved. Keeps the expectations reined in and the good news/bad news is taken in small doses over many runs. It's a lot less of an adrenaline rush but at my age that is probably a good thing.

 

[AfewUniversesBelowNormal]

Dec 20/21 may bust wet, because that is the pattern, began Dec 8. 

[showmethesnow]

58 minutes ago, Ralph Wiggum said:

NAM keeps ticking the midweek system Northward fwiw. Not sure if this keeps ticking we move the boundary and cold air N as well or if nosing HP would allow for overunning to happen. Probably nothing but we've seen a few times already where things worked in our favor. More for this particular region to keep an eye on anyway rather than my home region where we are probably too far N pending any unforseen major shifts. Just something to watch anyway.

Not sure how I feel about it. Brought this period of time up last Sunday as having some potential but the globals so far have been pretty unenthusiastic. Also have the deal with cold chasing warm to boot. Now if it was one of the globals doing this and not the NAM my interest would be perking up much more. But until then I will just keep a half eye on it with really no expectations.

[Ji]

19 hours ago, PhineasC said:

Screw precip on Christmas. It just causes cancellations and messes anyway. Give me clear and chilly, please. 40 - 45 degrees as a high would be fine.

12z GFS looks like an unfolding disaster and another radical change

[mitchnick]

Let me ninja JI... Gfs is a disaster