Holidays 2017-18 Mid-Long Range Disco

[Bob Chill]

24 minutes ago, WinterWxLuvr said:

Snowfall maps are ridiculous, and the snowfall mean is even more so.  And I think that applies close in as well.  Precip maps, h5 maps, h7 maps, h850 maps, precip tot maps, all that is good stuff.  Not the snow maps.  Those are "feel good"  maps, nothing more. 

I can't like this post enough. All a snowmap is is an algorithm based on basic surface and midlevel panels. A much better way to go is to analyze those panels yourself and determine how much precip falls as each precip type. Look at soundings for warm noses at intermediate levels like 925, 800, etc. That used to be my favorite exercise with Matt and Ian before snowmaps came out. This thread is a disaster. All snowmaps and no real analysis. 

[Conway7305]

I’m still learning here so forgive my rookie observations.  This morning the NAO index has  several more points potentially negative towards end of December into the New Year. I know there quite a few positive points but yesterday didn’t have any negative plots.  Hope this a trend. It should help our chances with any storm next week if we go negative. Just my observation.  

 

 

[BristowWx]

1 minute ago, Conway7305 said:

I’m still learning here so forgive my rookie observations.  This morning the NAO index has  several more points potentially negative towards end of December into the New Year. I know there quite a few positive points but yesterday didn’t have any negative plots.  Hope this a trend. It should help our chances with any storm next week if we go negative. Just my observation.  

 

 

its great but always proves elusive. 

[aldie 22]

2 minutes ago, Conway7305 said:

I’m still learning here so forgive my rookie observations.  This morning the NAO index has  several more points potentially negative towards end of December into the New Year. I know there quite a few positive points but yesterday didn’t have any negative plots.  Hope this a trend. It should help our chances with any storm next week if we go negative. Just my observation.  

 

 

Transition periods can be very fun around here

[Bob Chill]

What we know about the upcoming period after Christmas is a large/moisture laden shield of overrunning precip out in front of a pac shortwave is becoming more likely each day that passes. The signal first showed up 3-4 days ago and isn't budging in time. 

What we know about our climo is that any time you have strong waa flow out in front of a shortwave, the midlevels are under attack. I keep hearing "CAD is underdone" but CAD is only between the surface and 850mb tops. When 850 winds are ripping out of the southwest, the midlevels are warming regardless of the surface. It can be 18 degrees at the surface and we can flip to ZR or PL. It happens an this is the kind of setup that does it. I personally didn't think the 6z run was good at all. It's close to a heck of a lot of rain and very little frozen. 

So we know that there is probably going to be a shield of overrunning at some point next week. It's also probably that a shortwave is probably going to traverse the country. Lastly, this type of setup can be a big precip producer. 

What we don't know is all the important stuff like what track the shortwave takes, track of SLP, and the depth and temperature of the antecedent airmass, 

People are drooling over the 6z gefs and all I see is a primary making it to or north of our latitude west of the apps with a long duration waa precip shield. Not to mention we lose the column for a while. The snowmaps look pretty but the setup isn't that good at all for a legit cold snowstorm. 

Our serious and big events are CCB type of deals. GFS doesn't give us that. The furthest north we want a low to get is northern ky/southern WV before a jump. I do think this is very possible and it's a long way away from knowing how this is going to play out. Just think about how many shifts @ h5 we've seen for Christmas since it hit 144hr leads. Since this event appears to be significant, it's going to drive some people to the brink. 

[CAPE]

5 minutes ago, Bob Chill said:

What we know about the upcoming period after Christmas is a large/moisture laden shield of overrunning precip out in front of a pac shortwave is becoming more likely each day that passes. The signal first showed up 3-4 days ago and isn't budging in time. 

What we know about our climo is that any time you have strong waa flow out in front of a shortwave, the midlevels are under attack. I keep hearing "CAD is underdone" but CAD is only between the surface and 850mb tops. When 850 winds are ripping out of the southwest, the midlevels are warming regardless of the surface. It can be 18 degrees at the surface and we can flip to ZR or PL. It happens an this is the kind of setup that does it. I personally didn't think the 6z run was good at all. It's close to a heck of a lot of rain and very little frozen. 

So we know that there is probably going to be a shield of overrunning at some point next week. It's also probably that a shortwave is probably going to traverse the country. Lastly, this type of setup can be a big precip producer. 

What we don't know is all the important stuff like what track the shortwave takes, track of SLP, and the depth and temperature of the antecedent airmass, 

People are drooling over the 6z gefs and all I see is a primary making it to or north of our latitude west of the apps with a long duration waa precip shield. Not to mention we lose the column for a while. The snowmaps look pretty but the setup isn't that good at all for a legit cold snowstorm. 

Our serious and big events are CCB type of deals. GFS doesn't give us that. The furthest north we want a low to get is northern ky/southern WV before a jump. I do think this is very possible and it's a long way away from knowing how this is going to play out. Just think about how many shifts @ h5 we've seen for Christmas since it hit 144hr leads. Since this event appears to be significant, it's going to drive some people to the brink. 

I liked the 0z EPS a lot. Pretty sweet run for this lead time. Quite a few members have significant frozen over us and/or to our south late next week into the following weekend. I like seeing the southern solutions at this range. Should be an active and fun (and probably nerve-racking lol) period ahead.

[mappy]

32 minutes ago, Bob Chill said:

I can't like this post enough. All a snowmap is is an algorithm based on basic surface and midlevel panels. A much better way to go is to analyze those panels yourself and determine how much precip falls as each precip type. Look at soundings for warm noses at intermediate levels like 925, 800, etc. That used to be my favorite exercise with Matt and Ian before snowmaps came out. This thread is a disaster. All snowmaps and no real analysis. 

well that you can see  

[pasnownut]

To my eyes the 06z GEFS 500/700 panels look much better for 12/28 than they did a day ago.  More of an split flow overrunning deal as we dont see it close off in the SW like it showed yesterday.  What that boils down to??

Just need to be on the right side of the boundary.

[midatlanticweather]

23 minutes ago, Bob Chill said:

What we know about the upcoming period after Christmas is a large/moisture laden shield of overrunning precip out in front of a pac shortwave is becoming more likely each day that passes. The signal first showed up 3-4 days ago and isn't budging in time. 

What we know about our climo is that any time you have strong waa flow out in front of a shortwave, the midlevels are under attack. I keep hearing "CAD is underdone" but CAD is only between the surface and 850mb tops. When 850 winds are ripping out of the southwest, the midlevels are warming regardless of the surface. It can be 18 degrees at the surface and we can flip to ZR or PL. It happens an this is the kind of setup that does it. I personally didn't think the 6z run was good at all. It's close to a heck of a lot of rain and very little frozen. 

So we know that there is probably going to be a shield of overrunning at some point next week. It's also probably that a shortwave is probably going to traverse the country. Lastly, this type of setup can be a big precip producer. 

What we don't know is all the important stuff like what track the shortwave takes, track of SLP, and the depth and temperature of the antecedent airmass, 

People are drooling over the 6z gefs and all I see is a primary making it to or north of our latitude west of the apps with a long duration waa precip shield. Not to mention we lose the column for a while. The snowmaps look pretty but the setup isn't that good at all for a legit cold snowstorm. 

Our serious and big events are CCB type of deals. GFS doesn't give us that. The furthest north we want a low to get is northern ky/southern WV before a jump. I do think this is very possible and it's a long way away from knowing how this is going to play out. Just think about how many shifts @ h5 we've seen for Christmas since it hit 144hr leads. Since this event appears to be significant, it's going to drive some people to the brink. 

Great analysis Bob. I cannot agree more about the need to understand the upper levels. This has the look of a thump to rain to me too. It was way too close to the edge for snow. It is going to be an interesting week.  

[Bob Chill]

9 minutes ago, C.A.P.E. said:

I liked the 0z EPS a lot. Pretty sweet run for this lead time. Quite a few members have significant frozen over us and/or to our south late next week into the following weekend. I like seeing the southern solutions at this range. Should be an active and fun (and probably nerve-racking lol) period ahead.

EPS looks fantastic. Like too good. lol. Back to back big ones....it can only go downhill from here. 

[Bob Chill]

1 minute ago, midatlanticweather said:

Great analysis Bob. I cannot agree more about the need to understand the upper levels. This has the look of a thump to rain to me too. It was way too close to the edge for snow. It is going to be an interesting week.  

Luckily every single op is going to be wrong in some way if not completely. One thing I've noticed about the GEFS is that it really wants to amp everything in the mid range but things get flatter as we move forward in time. Same with the GFS op. Could be the higher resolution from the last upgrade causing it. 

Right now we have the Euro op/EPS squarely in our corner. Even with the squashed solution on the op last night. That's in our favor too. Moreso than the GFS. We don't want to play with fire like that. 

[aldie 22]

3 minutes ago, Bob Chill said:

EPS looks fantastic. Like too good. lol. Back to back big ones....it can only go downhill from here. 

Climo almost always wins....almost

[frd]

7 minutes ago, Bob Chill said:

EPS looks fantastic. Like too good. lol. Back to back big ones....it can only go downhill from here. 

Bob,  do you think that one one single factor in having a significant Mid Atlantic snow event later next week is the rather large 50 50 Low the EPS has ?

I mean we lack certain indices in our favor, yet that one overwhelming feature, the 50 50 Low ,  keeps the High and the cold air locked in place. Helps with temps and keeping the storm from coming too far West  

 

[Bob Chill]

2 minutes ago, leesburg 04 said:

Climo almost always wins....almost

Climo has learned us a lot of lessons over the years. You could probably make an accurate forecast right now....mixed event most likely and no event or all rain less likely. 

[pasnownut]

2 minutes ago, Bob Chill said:

Luckily every single op is going to be wrong in some way if not completely. One thing I've noticed about the GEFS is that it really wants to amp everything in the mid range but things get flatter as we move forward in time. Same with the GFS op. Could be the higher resolution from the last upgrade causing it. 

Right now we have the Euro op/EPS squarely in our corner. Even with the squashed solution on the op last night. That's in our favor too. Moreso than the GFS. We don't want to play with fire like that. 

Thats what I was implying regarding the 6z GEFS.  Verbatim if it can trend south as shown, it would put many on a more favorable trajectory for the 28/29th overruning deal.  That  would also force a transfer further SW if it would be a Miller B.  Miller B's are scary in the best of setups for our region (to me anyways.)

 

[Bob Chill]

2 minutes ago, frd said:

Bob,  do you think that one one single factor in having a significant Mid Atlantic snow event later next week is the rather large 50 50 Low the EPS has ?

I mean we lack certain indices in our favor, yet that one overwhelming feature, the 50 50 Low ,  keeps the High and the cold air locked in place. Helps with temps and keepinging the storm from coming too far West  

 

We actually do have legit blocking. EPS/GEFS both show a -AO leading in and even a hint of a bootleg -NAO  so I would say this setup is probably the best we've seen since Jan 16

 

The 2 panels above are very similar but obviously the EPS has a stronger blocking ridge in between GL and Hudson. Going by verification, the EPS is probably more right but we've seen the gefs so well before so tossing the southern ridge idea isn't the best way to go. 

 

There are some good check marks with this setup: -AO, 50/50, banana or strong HP to the N, decent antecedent airmass. Inside of the details and our latitude makes it impossible to spike any footballs. 

 

 

[BristowWx]

2 minutes ago, pasnownut said:

Thats what I was implying regarding the 6z GEFS.  Verbatim if it can trend south as shown, it would put many on a more favorable trajectory for the 28/29th overruning deal.  That  would also force a transfer further SW if it would be a Miller B.  Miller B's are scary in the best of setups for our region (to me anyways.)

 

But you are like the farthest north of everyone...if you are scared then we don't have a prayer 

[Bob Chill]

3 minutes ago, pasnownut said:

Thats what I was implying regarding the 6z GEFS.  Verbatim if it can trend south as shown, it would put many on a more favorable trajectory for the 28/29th overruning deal.  That  would also force a transfer further SW if it would be a Miller B.  Miller B's are scary in the best of setups for our region (to me anyways.)

 

The miller B's that scare the heck out of me are the ones with a moisture starved NS shortwave rounding the base and THEN getting going. This "should" be a well developed system well west of here. Models are showing a well developed pac shortwave with plenty of precip getting forced under strong HP. Even if it's a northern WV coastal jump, both our yards get good precip regardless. I think we can all live with that. If the transfer happens in KY to the coast then both our areas get under the pivot and CCB. Feb 2010 comes to mind but not nearly the same magnitude. 

[mappy]

no one should be scared of anything regarding an event over a week away

[clskinsfan]

5 minutes ago, pasnownut said:

Thats what I was implying regarding the 6z GEFS.  Verbatim if it can trend south as shown, it would put many on a more favorable trajectory for the 28/29th overruning deal.  That  would also force a transfer further SW if it would be a Miller B.  Miller B's are scary in the best of setups for our region (to me anyways.)

 

It depends where the transfer takes place. If it happens far enough south we can get bombed. And that is more likely with a southern stream vort. Where we run into problems is when a clipper jumps right over top of us. We get robbed of both the clippers precip and the coastals.

[clskinsfan]

1 minute ago, Bob Chill said:

The miller B's that scare the heck out of me are the ones with a moisture starved NS shortwave rounding the base and THEN getting going. This "should" be a well developed system well west of here. Models are showing a well developed pac shortwave with plenty of precip getting forced under strong HP. Even if it's a northern WV coastal jump, both our yards get good precip regardless. I think we can all live with that. If the transfer happens in KY to the coast then both our areas get under the pivot and CCB. Feb 2010 comes to mind but not nearly the same magnitude. 

And of course Bob beat me to it again

[aldie 22]

1 minute ago, mappy said:

no one should be scared of anything regarding an event over a week away

Scarred?

[Ger]

3 minutes ago, BristowWx said:

But you are like the farthest north of everyone...if you are scared then we don't have a prayer 

I don't think Lancaster County (esp considering how big it is) does all that much better during many/most Miller Bs. The key is to be North AND East.  

[Bob Chill]

3 minutes ago, leesburg 04 said:

Scarred?

Not me. Skerrd maybe

[Scarlet Pimpernel]

43 minutes ago, Bob Chill said:

 

What we know about our climo is that any time you have strong waa flow out in front of a shortwave, the midlevels are under attack. I keep hearing "CAD is underdone" but CAD is only between the surface and 850mb tops. When 850 winds are ripping out of the southwest, the midlevels are warming regardless of the surface. It can be 18 degrees at the surface and we can flip to ZR or PL. It happens an this is the kind of setup that does it. I personally didn't think the 6z run was good at all. It's close to a heck of a lot of rain and very little frozen. 

 

I was thinking the same exact thing when I looked at this earlier, Bob.  First thing this morning I checked the overnight/early morning discussions and saw lots of pretty maps and "wow!" comments, and thought maybe things were looking pretty good.  Then I went and checked the details of the 06Z GFS and didn't get all the hype.  Certainly it looked great for those much farther west and north.  And yeah, here in the 'burbs or closer in, snow and then potentially a good bit of ice--for awhile.  But then we lose the column down to the surface and there's a good period of all rain before it cools off again.  That tempered the enthusiasm for sure.  Plus, like you said, I don't like seeing the low go way to our northwest like that; we're very close to not even getting much on the front end even with that set-up.  It's better than 00Z, but still.  I'd rather see a nice front-end of snow followed only by sleet/ice if we have to transition, rather than going to cold rain for hours.

Now, that thing the 06Z GFS showed at the end of its run, the first week of the New Year...I'll definitely agree that was rather pretty to look at and dream about! 

[pasnownut]

15 minutes ago, BristowWx said:

But you are like the farthest north of everyone...if you are scared then we don't have a prayer 

Fair point bud....but in truth, in Miller B's i think MBY gets a similar fate to many in this forum.  Not much difference if I'm at the middle to upper end of the dry slot, and many of you are just smack in the middle.  Way southern crew....I just feel for ya.  Hope we can agree on that.

While I know to some I'm "that guy" in here, I'd like to think my tone has been one for the MA, as i fall far more into this region then many of my brethren in my "true home" forum wise.  Dont want to banter about subforum stuff, but like I've said before, I pull way more for the MA crew, cause if you guys are happy, usually i share in some of it.

 

Now get back to working yoru mojo for "Your" storm.  

Nut

 

[pasnownut]

20 minutes ago, Ger said:

I don't think Lancaster County (esp considering how big it is) does all that much better during many/most Miller Bs. The key is to be North AND East.  

thank you.  Some people act like i'm from Vermont/Boston...while my fate is so often similar to most here...and of the last few years, its often been worse while i've watched you guys have epic Marchs etc...blah blah blah.  All good.

And tell the Word Police that scared is just a term....not reality.  Good lord...put the coffee down.

[Bob Chill]

FWIW- GFS is better with ridging along the west coast d4-5 than previous runs. Should back off on the oil dig with the SW of our dreams. 

[Bob Chill]

Much better progression on the GFS. Totally dropped the big dig idea. Now looks like a conventional way we get cold/snow in these parts. It will change a million more times but getting rid of the big dig/cut progression will put people at ease. 

[showmethesnow]

The strong ridging in the central/eastern US should be really damped down without the trough digging into the SW.