December Forecast Discussion

[SnowGoose69]

Correct me if im wrong, but are you saying that you think the cold will be transient the first week of January? Then we go back to at or above normal temp pattern? If so the pattern the rest of the board is excited about will not have much time to work....

 

The Pac jet has been underestimated at times, its not entirely impossible that we will flip for a short time and then go back to a zonal pattern...I don't think its likely but with that QBO and Pac jet it could happen.

[SnoSki14]

The Pac jet has been underestimated at times, its not entirely impossible that we will flip for a short time and then go back to a zonal pattern...I don't think its likely but with that QBO and Pac jet it could happen.

Given how long we've waited for a pattern change that would be a huge kick in the you know what unless we manage to get a snow event prior to the pattern reverting back to zonal. Pray to god this doesn't happen. 

 

The blocking is so encouraging but we can't assume everything the models show beyond a certain time frame whether it be the gfs, euro, or their ensembles is going to play out exactly as shown. They are still likely to be less accurate until the transition is complete because there are way too many variables to figure out. 

[Radders]

As one might expect, the Euro Ensembles are more muted than the Op with the extent of the cutter and the propensity of the SE ridge, so there are probably some different solutions on the table.  

[Allsnow]

As one might expect, the Euro Ensembles are more muted than the Op with the extent of the cutter and the propensity of the SE ridge, so there are probably some different solutions on the table.

To me what's important is everything after the 28th. The next two will be cutters either way u slice it...Its highly likely nyc finishes december with 1 inch of snow

[Radders]

To me what's important is everything after the 28th. The next two will be cutters either way u slice it...Its highly likely nyc finishes december with 1 inch of snow

Agreed.  And the second storm will probably cut, or be marginal at best.. If we get lucky and the second storm doesn't cut, it isn't going to make much difference to the outcome post 12/28 - The post 12/28 period still looks primed for potential for wintry events.  Models are going to struggle with the evolution of the second cutter until they have fully resolved the outcome from the Xmas grinch storm.  

[Doorman]

DM, you make interesting posts, but I've noticed that you exclusively use NECP guidance which can be very dangerous considering it's relatively poor scores compared to the CMC and especially ECMWF guidance. 

 

http://www.tropicaltidbits.com/analysis/models/ecmwf-ens/2014121912/ecmwf-ens_z500_mslp_eus_11.png

 

 

 

SRA  take a look 

euro ens  

Flat on its back, in a black Cadillac .....

DOA for metro snowstorm  - imho

 

GEPS

http://www.tropicaltidbits.com/analysis/models/gem-ens/2014121900/gem-ens_uv250_eus_41.png

 

 

three maps

same flaps

[Superstorm93]

Chins up lads!

 

00z GEFS actually has a very nice pattern setting up for us over the next 6-10 days. Seeing the EPO go negative like that always gets my full attention, especially with how much of an impact it made last year. Hopefully things will work themselves out in the west, but this definitely isn't a bad look. 

[NYCSNOWMAN2020]

Would like to see snow squalls not rain squalls ugh...

[CIK62]

The last two GFS runs  0Z,  06Z  are showing no measurable snow till the 12/30--01/4 period in NYC.    We do better with the 2mT's which are basically below 32 most of the time (day and night) starting near 12/28.    In addition, the latest GFSx shows a whopping +9deg. anomaly over the next 7 days!   I am estimating that by the time we have our next below normal temp. day,   December 2014 will be +2.8degs. for the month, with maybe 4 days to erase this by being 20degs. below normal each of those days.

 

But as we look ahead to Jan. now all I see are below normal temps. during the entire month except near mid-month.  However looks dry, with a storm track to our southeast most of the time, except you guessed it, mid-month. 

[bluewave]

Even though the EPO is forecast to finally drop negative, it may be a challenge keeping

the Western Atlantic Ridge suppressed for very long with all that warm water east of us.

It looks like the WAR does get suppressed close to New Year's Eve and we see a

colder gradient pattern set up into the beginning of January. But the longer range

guidance has been hinting at a return of the WAR near the end of the 15 day period.

Still a but early to know for certain, but it will be something to monitor. 

 

 

[PB GFI]

Even though the EPO is forecast to finally drop negative, it may be a challenge keeping

the Western Atlantic Ridge suppressed for very long with all that warm water east of us.

It looks like the WAR does get suppressed close to New Year's Eve and we see a

colder gradient pattern set up into the beginning of January. But the longer range

guidance has been hinting at a return of the WAR near the end of the 15 day period.

Still a but early to know for certain, but it will be something to monitor. 

 

sst.gif

 

500.gif

When I see a 3 SD below normal EPO and AO with a neg PNA I would assume a gradient pattern is probably at work.

It worked on 93 94 and is a lot more fun to track than cold and dry .

I will take my chances if we can park the vortex near Hudson bay.

[MJO812]

When I see a 3 SD below normal EPO and AO with a neg PNA I would assume a gradient pattern is probably at work.

It worked on 93 94 and is a lot more fun to track than cold and dry .

I will take my chances if we can park the vortex near Hudson bay.

It also worked last winter for a while.

[REDMK6GLI]

It also worked last winter for a while.

The strong -EPO is what saved last winter since the teleconnectors all around sucked. if we CAN get the -EPO/AO to combat the SE ridge it may work again though. Wouldnt hurt if we got a strong west based -NAO either, after december 2010 its pretty much taken a hiatus

[MJO812]

The strong -EPO is what saved last winter since the teleconnectors all around sucked. if we CAN get the -EPO/AO to combat the SE ridge it may work again though. Wouldnt hurt if we got a strong west based -NAO either, after december 2010 its pretty much taken a hiatus

The strong -NAO really saved the 2010-2011 winter.

[MJO812]

So why aren't things going to plan exactly. Based on historical data we shouldn't have this much trouble establishing a favorable pattern especially because all signs since October greatly favored cold and above normal snow.

Things are going as planned. The pattern is slowly changing into a favorable one and should be seen on the models by the last week of December.

[CIK62]

Even though the EPO is forecast to finally drop negative, it may be a challenge keeping

the Western Atlantic Ridge suppressed for very long with all that warm water east of us.

It looks like the WAR does get suppressed close to New Year's Eve and we see a

colder gradient pattern set up into the beginning of January. But the longer range

guidance has been hinting at a return of the WAR near the end of the 15 day period.

Still a but early to know for certain, but it will be something to monitor. 

 

sst.gif

 

500.gif

I see what you mean about the ridge trying to restore itself.    850mb gph Now 1460m, in 16 days 1560m    500mb gph Now 5540m, in 16 days  5610m.   I think that might make it about 6 degs. warmer then than today is other things being equal.

[MJO812]

I see what you mean about the ridge trying to restore itself.    850mb gph Now 1460m, in 16 days 1560m    500mb gph Now 5540m, in 16 days  5610m.   I think that might make it about 6 degs. warmer then than today is other things being equal.

That's if this guidance is even right about that. We are talking 10+ days here.

[bluewave]

When I see a 3 SD below normal EPO and AO with a neg PNA I would assume a gradient pattern is probably at work.

It worked on 93 94 and is a lot more fun to track than cold and dry .

I will take my chances if we can park the vortex near Hudson bay.

 

We know that a gradient pattern is coming near the end of the day 10 period which has been well

advertised. If the last few years have taught us anything, we can capitalize on a good pattern while we

have it. It won't take much for a low to roll from Amarillo to the MA and at least deliver a frozen front

end thump if we get decent Arctic HP north of the Great Lakes. But the duration of the gradient pattern

is still up in the air no pun intended. A flat SE Ridge beyond the day 8-15 wouldn't be too bad, but 

just enough strength would push the best snow potential up into New England maybe by the second

week of January. But that is pretty far out in time to speculate about. I would just like to start

getting some points on the board to begin January if possible.

[White Gorilla]

Damn, I am learning a lot from you guys! Keep up the great discussions!

[PB GFI]

We know that a gradient pattern is coming near the end of the day 10 period which has been well

advertised. If the last few years have taught us anything, we can capitalize on a good pattern while we

have it. It won't take much for a low to roll from Amarillo to the MA and at least deliver a frozen front

end thump if we get decent Arctic HP north of the Great Lakes. But the duration of the gradient pattern

is still up in the air no pun intended. A flat SE Ridge beyond the day 8-15 wouldn't be too bad, but

just enough strength would push the best snow potential up into New England maybe by the second

week of January. But that is pretty far out in time to speculate about. I would just like to start

getting some points on the board to begin January if possible. Maybe we can repeat last December 14th.

http://mp1.met.psu.edu/~fxg1/NARR/2013/us1214.php

Amarillo to DC you know I love that track.

And Dec 14 illustrates my point. NEG EPO SE ridge does work for us.

I will admit no 2 patterns are exactly the same but the rules usually are.

77 78 looked like this that Dec so my hope as its an analog year we follow it in jan and Feb

[bluewave]

Amarillo to DC you know I love that track.

And Dec 14 illustrates my point. NEG EPO SE ridge does work for us.

I will admit no 2 patterns are exactly the same but the rules usually are.

77 78 looked like this that Dec so my hope as its an analog year we follow it in jan and Feb

 

At least we know we are going to get the -EPO to deliver the cold day 8-15. It will all come down to what we

can put together during the first week of January. I just hope we can buy some time and keep that SE Ridge

suppressed long enough. It will be interesting to see if the long range stuff holds onto the SE Ridge suppression

longer, or we see it rebound during the second week of January. 

[robPAwx]

Light flurries here in Union, NJ.

[Zelocita Weather]

Yup...a few flakes in Essex county as well...

[PB GFI]

At least we know we are going to get the -EPO to deliver the cold day 8-15. It will all come down to what we

can put together during the first week of January. I just hope we can buy some time and keep that SE Ridge

suppressed long enough. It will be interesting to see if the long range stuff holds onto the SE Ridge suppression

longer, or we see it rebound during the second week of January. 

 

Last years cold from an extended NEG EPO was so overpowering I doubt we see that again this year . Many don`t realize it was a top 8 snowy winter in NYC but number a 1 or 2 ranked snow and cold winter for so many in the upper mid west and around the lakes . That  vortex got trapped last year way longer than anyone could have anticipated.

 

I  expect we get a few good systems to cut S , we pull back and do it again .

 

To expect last years totals and departures would be way to much to ask .

[MJO812]

Flurries here

[robPAwx]

The flurries actually picked up here, but no accumulations

[doncat]

Wow steady temps today...thought my thermo was broken lol..

[Guest Pamela]

Definitely appears as if there will be periods of light snow with minor accumulations...especially out over Long Island & Connecticut...later today into tomorrow.

[PB GFI]

Very close day 8  for the areas just  N on the 12z Euro . Would watch to see how that wave progresses as we get closer .

[MJO812]

Gefs has a nice storm signal near NYE