Rising confidence in favorable period for snow Dec 15 - Jan 1

[IsentropicLift]

Lots of uncertainty on the latest teleconnections after mid-month, but the general concensus is for the PNA to remain in positive territory and for the NAO to move closer to neutral. Too much uncertainty exists for the AO with the various ensembles nearly split, with a slight lean into negative territory.

 

[bluewave]

The problem already showing up in the Euro ensembles around day 10 is that

there won't be a 50/50 in place. Any energy coming out of the southern stream

will come up against a high exiting the coast to the north. So it will probably

ride close to the coastal plain like the current event with plenty of mild onshore

flow for coastal sections. That's why we need a strong -AO/-NAO pattern

to keep that 50/50 and cold in place ahead of the storm which the models

aren't showing.

 

[White Gorilla]

KNYC

AVERAGE MONTHLY: 40.7   ( Actual number is 40.65 and will be adjusted at months end )

DPTR FM NORMAL:  -0.3  That`s normal and never the torch that was advertised .    And that includes Dec 1 splits  of  65  42 otherwise the last 8 days are no where AN.  I posted the next 9 days surface temps yesterday off the 12z run back a few  .

 

http://www.nws.noaa.gov/climate/getclimate.php?wfo=okx

 

 

Don`t worry about the whole country , you live in the NE and the EUROPEAN continues to push troughs through the lakes . It`s only Dec 10 and the pattern looks to progress over the next 10 days with 2 storms showing up on the European ensembles . Do they turn the corner ? To early to tell but the European is just cold enough going into Christmas week .

Key phrase is "cold enough". Moving forward we will also have climo in our favor. I would worry about too cold and suppression if we had major arctic outbreaks. With an active storm track that has been near the coast, it won't be long before a snowstorm IMO.

[Dsnowx53]

The problem already showing up in the Euro ensembles around day 10 is that

there won't be a 50/50 in place. Any energy coming out of the southern stream

will come up against a high exiting the coast to the north. So it will probably

ride close to the coastal plain like the current event with plenty of mild onshore

flow for coastal sections. That's why we need a strong -AO/-NAO pattern

to keep that 50/50 and cold in place ahead of the storm which the models

aren't showing.

 

ecmwf-ens_mslpa_nhem_11.png

 

 

To be fair, an ensemble mean is going to mute any signal of a transient rex/omega block. Not that we're going to see some strong rex/omega block magically appear on the models, but I do think we have a shot at a rex/omega block moving into Central Canada a the same time that a storm slides across the southern tier (a few OP runs have shown this, including last night's Euro). This could hopefully set up some sort of 50/50 low feature.

 

Now if we don't get a transient rex/omega block, then a snow threat is not going to work out. 

[PB GFI]

The problem already showing up in the Euro ensembles around day 10 is that

there won't be a 50/50 in place. Any energy coming out of the southern stream

will come up against a high exiting the coast to the north. So it will probably

ride close to the coastal plain like the current event with plenty of mild onshore

flow for coastal sections. That's why we need a strong -AO/-NAO pattern

to keep that 50/50 and cold in place ahead of the storm which the models

aren't showing.

 

ecmwf-ens_mslpa_nhem_11.png

That southern stream is 2 or 3 systems strong and not 1 and done . It`s very possible one rains on the coast , its very possible that one misses and then there is a possibility that one of these get us .

 

Pos PNA while you move the center point at 500 MB into Hudson Bay . An active Southern Jet and yes it`s just cold enough .

 

You are inviting trouble with this set up . 

[SnowGoose69]

The tendency has been to show the colder solutions longer range only to get warmer with out recent storms as we

got closer in. Until I see a solid -AO/-NAO pattern developing to push back against that +EPO, I am not optimistic

about any significant snows for the coast. Interior sections always have more leeway in unfavorable patterns.

 

My guess is that is simply the pattern change being delayed as is usually the case...the GFS attempted to put us into the current pattern we are in a good 10 days or so early back in November its likely doing the same now.

[alwaysready126]

Reds are fading away.....

[REDMK6GLI]

Reds are fading away.....

This another great sign. Also in response to paul the higher heights around hudson bay usually leads to a notable trough on the EC. We just need it perfectly timed where we dont have in hug the coast like the storm did yesterday. I do feel that the +PNA and NAO heading towards atleast nuetral territory may help us. The cold air really isnt impressive but not warm enough where we will rain the rest of the month no matter what setup/storm on the EC. Atleast we have a nice parade of storms to track come christmas week. I always welcome an active southern stream in a weak el nino year

[alwaysready126]

This another great sign. Also in response to paul the higher heights around hudson bay usually leads to a notable trough on the EC. We just need it perfectly timed where we dont have in hug the coast like the storm did yesterday. I do feel that the +PNA and NAO heading towards atleast nuetral territory may help us. The cold air really isnt impressive but not warm enough where we will rain the rest of the month no matter what setup/storm on the EC. Atleast we have a nice parade of storms to track come christmas week. I always welcome an active southern stream in a weak el nino year

Am I correct in saying that the EC is one of the only places that usually benefits from a weak el nino?

[REDMK6GLI]

Am I correct in saying that the EC is one of the only places that usually benefits from a weak el nino?

Yea weak el nino is considered by many to be "the weenies pot of gold". Towards the 20th and on we will continue to step down to a more favorable cold and snowy pattern into new years. Also i PM'd you yesterday apologizing for my personal attack against you, it was wrong that i did that and i apologize for it

[wolfsheepsheadbay]

REDMK6GLI, just wanted to call out that your posts on the past few pages have been stellar and spot on. You've clearly learned quite a good deal about pattern forecasting even since last year. Keep it up.

[REDMK6GLI]

REDMK6GLI, just wanted to call out that your posts on the past few pages have been stellar and spot on. You've clearly learned quite a good deal about pattern forecasting even since last year. Keep it up.

Much appreciated, ive gotta give credit to all the major non-mets and mets alike for showing me some things whether right or wrong to help me get better at this. Paul (PB GFI) has helped me a good bit as well, hes a great asset here IMO.

That said going into christmas week we've had poorer antecedent airmasses and upper level setups that have produced snow even at the coast. We are in a weak el nino with a parade of storms staged to move across the southern tier of the CONUS. The +PNA has covered up some of our sins for the inland folks especially. if we can get that trough axis hopefully over the MS valley and ridge axis over Idaho we can get one of these to turn the corner and deliver the goods to all. This all despite a less than ideal setup on the EC currently.

[SnoSki14]

What this entire period has demonstrated and the reason why last winter was so cold and snowy is the power of the EPO. It appears to be the single greatest driver in our winter weather because it dictates our cold. Just look how a +EPO is torching Canada and a huge chunk of the CONUS and that has far greater effects than a -NAO or +PNA will ever have.

[PB GFI]

What this entire period has demonstrated and the reason why last winter was so cold and snowy is the power of the EPO. It appears to be the single greatest driver in our winter weather because it dictates our cold. Just look how a +EPO is torching Canada and a huge chunk of the CONUS and that has far greater effects than a -NAO or +PNA will ever have.

 

 

When you see those height anomalies they don`t equate to 2 m temps .

What` is 2SD  above normal in Manitoba is N in KNYC .  N and C  CANADA ARE NOT TORCHED .

And that`s where your air will be  aimed from with a pos PNA .

 

This is the next 7 days at Yellowknife .http://weather.gc.ca/city/pages/nt-24_metric_e.html 

This is the next 7 days at Saskatoon   http://weather.gc.ca/city/pages/sk-40_metric_e.html

This is the next 7 days at Thunder bay http://weather.gc.ca/city/pages/sk-40_metric_e.html   The warm  lasts 3 days

 

Stop looking for last years cold it was a 1 in a 10 year temp extreme . I am not sure if i saw 2013 - 2014 temps expected for  this winter but we don`t need it to be as cold as last year for it  to snow . You have to be patient .

This slightly BELOW NORMAL pattern that we have been in starts to turn around the 20th 

Dec 1- 14 at KNYC will finish below normal  .

[REDMK6GLI]

What this entire period has demonstrated and the reason why last winter was so cold and snowy is the power of the EPO. It appears to be the single greatest driver in our winter weather because it dictates our cold. Just look how a +EPO is torching Canada and a huge chunk of the CONUS and that has far greater effects than a -NAO or +PNA will ever have.

You really have to do better research before ONCE AGAIN posting stuff like this. While not totally wrong saying canada is "torched" is wrong. It isnt and by the 18-20th time frame on it will start cooling and wont take much to be below normal as a whole again. IMO your just digging for gold to find that reason to punt december. average out this month in the end in its totality and it will be below normal in CANADA and sufficient enough source for us to tap should a storm come up the coast once the southern stream opens up.

Like i said previously North America has had worse patterns than this and has still produced on the EC

[Stormlover74]

Another reason why you can't just look at the long range GFS operational...now it has snow next Sunday/Monday followed by very cold air behind it

[bluewave]

That southern stream is 2 or 3 systems strong and not 1 and done . It`s very possible one rains on the coast , its very possible that one misses and then there is a possibility that one of these get us .

 

Pos PNA while you move the center point at 500 MB into Hudson Bay . An active Southern Jet and yes it`s just cold enough .

 

You are inviting trouble with this set up . 

 

I was talking about the day 10 Euro ensemble mean. I don't like to speculate on storm details out to 360

which is more uncertain. But the (360) 12-25 map agrees with other long range guidance that the last week of 

the month should be a transition process. That's when I would be looking at potential for a small or even moderate frozen

event  all the way to the coast.

[REDMK6GLI]

I was talking about the day 10 Euro ensemble mean. I don't like to speculate on storm details out to 360

which is more uncertain. But the (360) 12-25 map agrees with other long range guidance that the last week of

the month should be a transition process. That's when I would be looking at potential for a small or even moderate frozen

event all the way to the coast.

Agree with this statement but i still wouldnt write off the period around the 17th on as well. Perfectly timed trough in the east going negative tilt would make lots of people happy on the EC maybe even NYC. Really dont want to see NYC wait until post Jan 1st for they're first 4"+ event since that usually isnt great historically for total winter accumulations compared to average.

Lots of opportunities before Dec. 31st that will be in the flow and coming to the EC. They cold air will be cold enough just have to get it right off the EC. Not the best pattern but we've done it with patterns less promising then this current one chris

[PB GFI]

I was talking about the day 10 Euro ensemble mean. I don't like to speculate on storm details out to 360

which is more uncertain. But the (360) 12-25 map agrees with other long range guidance that the last week of 

the month should be a transition process. That's when I would be looking at potential for a small or even moderate frozen

event  all the way to the coast.

 

Looking at the 10 day OP , I am curious to see if the ensembles continue to take the center east of the MISS so it get it`s feet wet . That said I agree that it`s going to be hard to keep a system all frozen on the coastal plain before the 20th as the set up looks like any LP that attacks the NE does so in the wake of a retreating HP and E winds rule the day .

 

Anything frozen would need something transient in Canada to accompany it . That`s not something the model is going to see 10 -15 days out .

However I do think this becomes more favorable after the 20th as the higher heights work it`s way N and may allow more arctic air into the pattern or at least " just enough " .

 

Think there are 2 systems to track over the next 10 days . 

[bluewave]

Agree with this statement but i still wouldnt write off the period around the 17th on as well. Perfectly timed trough in the east going negative tilt would make lots of people happy on the EC maybe even NYC. Really dont want to see NYC wait until post Jan 1st for they're first 4"+ event since that usually isnt great historically for total winter accumulations compared to average.

Lots of opportunities before Dec. 31st that will be in the flow and coming to the EC. They cold air will be cold enough just have to get it right off the EC. Not the best pattern but we've done it with patterns less promising then this current one chris

 

The big question is whether we can cash in on a small to moderate event during a transition process away

from the unfavorable pattern we have now? Or will we have to wait until the favorable pattern becomes more

established in early January? The one thing the analog composites suggest is that the most +EPO pattern

in an El Nino winter occurs in December. I am really not sure yet how long it will take for a more

favorable Atlantic side blocking pattern to emerge. 

[REDMK6GLI]

The big question is whether we can cash in on a small to moderate event during a transition process away

from the unfavorable pattern we have now? Or will we have to wait until the favorable pattern becomes more

established in early January? The one thing the analog composites suggest is that the most +EPO pattern

in an El Nino winter occurs in December. I am really not sure yet how long it will take for a more

favorable Atlantic side blocking pattern to emerge.

On the LR EURO you can see the higher heights being pushed further north. That is a good sign but i also want to start seeing the PV disturbed sooner rather than later and split to help kickstart the -NAO as well.

At this juncture with lag between strat. Warming regime and transfer to reflection via blocking (hope i worded that correctly) i cant see blocking taking hold later than early january. Until then i still think we have some transient windows albeit small for some snow opportunities for the immediate NYC area. No guarantees but im still optimistic regarding christmas week chris. Like ive said we've seen far worse thread the needle for us on the EC before.

Furthermore, SSTA warm pools on the west coast and alaska and off the EC atleast through analog comparison does show that atleast JFM below normal temps compared to normal should be centered from the MS river east. Doesnt hurt when we do get the blocking. That we have to return to when we get -EPO back into place and we can hopefully get that cross polar flow established again

[SnoSki14]

Good news is that after the NAO peaks at +2 it will steadily drop off. The last time we saw a peak that positive happened to switch to a negative NAO a couple months ago. Not saying that will happen this time but it should represent the gradual transition these next couple weeks.

[bluewave]

On the LR EURO you can see the higher heights being pushed further north. That is a good sign but i also want to start seeing the PV disturbed sooner rather than later and split to help kickstart the -NAO as well.

At this juncture with lag between strat. Warming regime and transfer to reflection via blocking (hope i worded that correctly) i cant see blocking taking hold later than early january. Until then i still think we have some transient windows albeit small for some snow opportunities for the immediate NYC area. No guarantees but im still optimistic regarding christmas week chris. Like ive said we've seen far worse thread the needle for us on the EC before.

Furthermore, SSTA warm pools on the west coast and alaska and off the EC atleast through analog comparison does show that atleast JFM below normal temps compared to normal should be centered from the MS river east. Doesnt hurt when we do get the blocking. That we have to return to when we get -EPO back into place and we can hopefully get that cross polar flow established again

 

The climo for El Nino winters is for the best potential of Atlantic side(AO-NAO) blocking to occur in January and February.

But the big unanswered question is how strong and the  exact location of that blocking? The wild card may be that

we didn't see a strong -AO pattern emerge sooner in December after the October signal. Most Decembers that followed

a strong -AO October like we just saw had much better blocking that we are seeing now. So I don't know how that

is going to play out in January and February. 

[REDMK6GLI]

Good news is that after the NAO peaks at +2 it will steadily drop off. The last time we saw a peak that positive happened to switch to a negative NAO a couple months ago. Not saying that will happen this time but it should represent the gradual transition these next couple weeks.

It WILL go negative and when it does the pattern will lock in. Once we get those higher heights around N. CANADA and GREENLAND we will start seeing more favorable conditions for snow on the EC. You can see on the LR the higher heights around hudson bay getting nudged north little by little on the models.

Those positive anomolies helped get this storm on the EC this week and in a +NAO regime that is making a run at +2 SD and it being a slow mover as well despite the lack of -NAO. That +PNA has really done its dirty work at making sure we have not torched, when in a +NAO state we are suppose to. LR is showing this step down and this month NYC despite a less than ideal pattern should see a 3"+ event, anything bigger is a bonus ATM. LOTS of potential heading into the meats and potatoes of december, one of them will make a run at us on the EC.

[REDMK6GLI]

The climo for El Nino winters is for the best potential of Atlantic side(AO-NAO) blocking to occur in January and February.

But the big unanswered question is how strong and the exact location of that blocking? The wild card may be that

we didn't see a strong -AO pattern emerge sooner in December after the October signal. Most Decembers that followed

a strong -AO October like we just saw had much better blocking that we are seeing now. So I don't know how that

is going to play out in January and February.

I will say this pull back was a bigger step that some imagined in the wrong direction. however, i cant see the lack of blocking occurring going forward through december and into JFM.

Do you by any chance have composites of NYC winters in a Weak El Nino with blocking averaging nuetral or slightly positive in december?. I can only imagine that its not that common of an occurence to not see any kind of blocking start to take hold once again in december after a blocking regime in october

[bluewave]

I will say this pull back was a bigger step that some imagined in the wrong direction. however, i cant see the lack of blocking occurring going forward through december and into JFM.

Do you by any chance have composites of NYC winters in a Weak El Nino with blocking averaging nuetral or slightly positive in december?. I can only imagine that its not that common of an occurence to not see any kind of blocking start to take hold once again in december after a blocking regime in october

 

Really too variable to be of any help. But the lack of a strong -AO response this December may be related to the

the general rise in the AO after March 2013. October was the first significant AO drop since March 2013.

Last winter we relied on the -EPO to pick up the slack which worked out very well.

 

AO index:

 

2013 -0.610 -1.007 -3.185 0.322 0.494 0.549 -0.011 0.154 -0.461 0.263 2.029 1.475

2014 -0.969 0.044 1.206 0.972 0.464 -0.507 -0.489 -0.372 0.102 -1.134 -0.530

[REDMK6GLI]

Really too variable to be of any help. But the lack of a strong -AO response this December may be related to the

the general rise in the AO after March 2013. October was the first significant AO drop since March 2013.

Last winter we relied on the -EPO to pick up the slack which worked out very well.

AO index:

2013 -0.610 -1.007 -3.185 0.322 0.494 0.549 -0.011 0.154 -0.461 0.263 2.029 1.475

2014 -0.969 0.044 1.206 0.972 0.464 -0.507 -0.489 -0.372 0.102 -1.134 -0.530

Yea the -EPO really helped salvage what couldve been a clunker of a winter last year with little if any support from the PNA,AO & NAO.

Have to watch the prospects of NYC not getting any measurable snowfall 4" or more for december. That historically doesnt bode well for annual snowfall totals for NYC. Weak El Nino or not if that happens january and february will have some work to do to finish above average if NYC enters Jan. 1st with .00" of snowfall YTD. IMO we have to really make the most of the poor airmass and upper air pattern in december

[TauntonBlizzard2013]

Yea the -EPO really helped salvage what couldve been a clunker of a winter last year with little if any support from the PNA,AO & NAO.

Have to watch the prospects of NYC not getting any measurable snowfall 4" or more for december. That historically doesnt bode well for annual snowfall totals for NYC. Weak El Nino or not if that happens january and february will have some work to do to finish above average if NYC enters Jan. 1st with .00" of snowfall YTD. IMO we have to really make the most of the poor airmass and upper air pattern in december

Does it really matter? NYC and places around the coast average so little little in December to begin with. How will that small a deficit be tough to overcome if a good pattern sets up moving forward

[alwaysready126]

Does it really matter? NYC and places around the coast average so little little in December to begin with. How will that small a deficit be tough to overcome if a good pattern sets up moving forward

The law of averages....  historically, if NYC gets no snow in December, I think the number is close to 90% that we get less than average snowfall for the remainder of the winter.  

[REDMK6GLI]

Does it really matter? NYC and places around the coast average so little little in December to begin with. How will that small a deficit be tough to overcome if a good pattern sets up moving forward

From a historical standpoint it would be fairly important. Chris i believe also posted that list or maybe Uncle W that showed the correlation between little or no snow decembers and what that contributed to the final season tally of annual snowfall. The list really wasnt very promising at all, who knows maybe with a weak el nino it may be a mute point and we jackpot JFM, BUT i wouldnt want to enter january with 0.00" of snowfall in NYC.