December and a Hint of January Pattern Discussion

[Bob Chill]

Anyone see the low pressure to the east of us at hour 162 on the Euro?  Temps are marginal (upper 30's) and precip looks limited at this point, but there is a nice high pressure over New England.  Something to watch?

 

Edit: Is that a subtropical system?

 

Not, it's a vort in the flow that blows up off the coast. It's been modeled with various solutions. This is just another solution. Airmass isn't even close though. Verbatim, snow is relegated to NNE only. 

 

Big cold blast behind the cutter afterwards though. It's going to be a variable month for sure until if/when we get some sort of feature to hold the cold more than 3 days. 

[lsukev]

Thanks for the reality check 

[Bob Chill]

Euro ensembles look half decent after the relaxation next week. Atlantic showing signs of improving. Warmish period looks short lived. 

 

One thing that is looking very likely is the northern plains are gonna be pretty dang cold for an extended period.

 

Nice to see that both the gefs and euro are leaning towards a relatively short lived "meh" period before moving back towards cooler and hopefully active period. There will be a big temp gradient setting up. Climo says we're probably going to be on the losing side but it's too far out to worry and it's nice to see substantial cold nearby. 

[PhineasC]

Euro ensembles look half decent after the relaxation next week. Atlantic showing signs of improving. Warmish period looks short lived. 

 

One thing that is looking very likely is the northern plains are gonna be pretty dang cold for an extended period.

 

Nice to see that both the gefs and euro are leaning towards a relatively short lived "meh" period before moving back towards cooler and hopefully active period. There will be a big temp gradient setting up. Climo says we're probably going to be on the losing side but it's too far out to worry and it's nice to see substantial cold nearby. 

I think the tone of the winter will be that through the swings, cold will usually win out. I think that could yield a fairly decent winter snow-wise, but nothing extraordinary. 15 inches of snow with one or two warning events would feel downright epic after the last two winters. It just seems like cold wants to win and the source regions have been filled with Arctic air rather than the Pacific air that we have seen in the recent past.

[PhineasC]

Have Siberia and Europe been cold? Seems like they have been having massive Arctic outbreaks and historic snow the last few years so if they are warm or normal that probably bodes better for us.

[Bob Chill]

Have Siberia and Europe been cold? Seems like they have been having massive Arctic outbreaks and historic snow the last few years so if they are warm or normal that probably bodes better for us.

 

No, Russia is pretty much entirely aoa for the last 3 weeks. Even moreso in the last 10 days or so. Coldest anomalies are centered around central and western Canada plus the very high latitudes thanks to a +NAO/AO. The cold has definitely been on our side of the globe and I'm encouraged for the same reasons you are. 

 

Canadian fronts will be colder than we've seen that last 2-3 years for the time being. About time right? 

 

ETA:

 

 

 

[HM]

models aren't that warm that 1st week of december..reallt depends where  the gradient sets up...we could be mid to upper 40s much of the week....though  I think a day or 2 of mid 50s or warmer is possibly in the cards

 

Makes sense. I still like mid-month trouble, despite my "el nino-forcing" taking a backseat for the time being. The Tropical Pacific is a mess right now, to say the least. Forcing exists from Africa to the Dateline and models have no freakin' clue what the MJO is doing. I have a feeling there is more cold to come after the relaxation.

 

I like 61-62 and you like 96-97. I think both had a pretty nasty mid-month cold shot, before xmas with 61 delivering snow.

[aldie 22]

Top analog now from the 12z GFS:

So this didn't workout....how accurate are these things?

[usedtobe]

So this didn't workout....how accurate are these things?

Who knows,  it helps that they are 5 day means as that tends to damp out the smaller scale harder to forecast features leaving only the larger scale ones.  However,  the GFS superens is better than the GFS version you showed as it takes into account lots of members with slightly different starting conditions while the gfs is a single model.  Last year, the supersen in general did a pretty good job of indicating the surface temp average versus the mean when you looked at the composite of the 10 analogs.  They also can give you an idea of how the pattern typically fairs in terms of snow. 

[aldie 22]

Who knows,  it helps that they are 5 day means as that tends to damp out the smaller scale harder to forecast features leaving only the larger scale ones.  However,  the GFS superens is better than the GFS version you showed as it takes into account lots of members with slightly different starting conditions while the gfs is a single model.  Last year, the supersen in general did a pretty good job of indicating the surface temp average versus the mean when you looked at the composite of the 10 analogs.  They also can give you an idea of how the pattern typically fairs in terms of snow.

Thank you

[uncle W]

1961-62 was much colder than 1996-97...DCA got 15" in 61-62 and 6.7" in 96-97...In NYC the biggest snowstorm came on Christmas eve...Newark got 10"...January was cold but had little snow...February had frequent snows the first three weeks...three of them were significant...there was some extreme blocking that year in March...There was the Ash Wednesday storm in early March 62...NYC got a little snow but had tidal flooding...1996-97 had two consecutive events with rain and snow the first week of December...It was not cold enough for a snowstorm...Had it come in January it would have been big...The next chance for heavy snow was on March 31st...Again it was to warm for heavy snow but had it come in January it would have been a blizzard...As analogs I have both on my list but 61-62 had some extreme blocking which might not happen this year...61-62 was almost a la nina year using the mei...1996-97 had a little weaker  negative mei reading...This year could end up with a plus neutral enso...The mei was slightly plus as of last month...1989-90 mei is a closer match to this year so far...

[yoda]

The GFS tonight would appear to advertise that the southern stream is not dead or dormant, it just decides to be active when it feels like it.  There is a wave that develops in the first few days of December... but it tracks off the SE coast and out to sea.  Looks like we get some kind of cutter Dec 6-7 and then maybe some wave development after that on the 8-9, but ofc, its slightly ever so warm even though there is a weak H in Quebec right where we would want it to be.

 

Out in h5 weenieland, GFS does build quite a large ridge out in the Pacific, so anything coming into the US will have to go up and over the ridge into W Canada and the Western US

 

http://mag.ncep.noaa.gov/NCOMAGWEB/appcontroller/data/gfs/00/gfs_namer_312_500_vort_ht.gif

 

Not a great pattern, but one I assume would be useful if the Atlantic decided to play nice.  At least the PV is on our side of the globe up in N Canada as well.

 

BTW, looking at Wes's weather education thread, is that a +PNA or a -PNA that the 00z GFS comes up with Days 11-15?

[HM]

1961-62 was much colder than 1996-97...DCA got 15" in 61-62 and 6.7" in 96-97...In NYC the biggest snowstorm came on Christmas eve...Newark got 10"...January was cold but had little snow...February had frequent snows the first three weeks...three of them were significant...there was some extreme blocking that year in March...There was the Ash Wednesday storm in early March 62...NYC got a little snow but had tidal flooding...1996-97 had two consecutive events with rain and snow the first week of December...It was not cold enough for a snowstorm...Had it come in January it would have been big...The next chance for heavy snow was on March 31st...Again it was to warm for heavy snow but had it come in January it would have been a blizzard...As analogs I have both on my list but 61-62 had some extreme blocking which might not happen this year...61-62 was almost a la nina year using the mei...1996-97 had a little weaker  negative mei reading...This year could end up with a plus neutral enso...The mei was slightly plus as of last month...1989-90 mei is a closer match to this year so far...

 

I wouldn't totally rule out the idea yet of a west -NAO based response to the PV diving into western Canada. This same thing occurred in 1961 and helped keep the East from being too "plus-side" for the month, despite the background being -PNA. I think the El Nino-push we've been seeing will continue and possibly have a stronger hold on the pattern mid-month.

 

Having said that, I don't think any of these analog years had quite the polar vortex strength that we have now. There has been some disruptions, on a fairly regular basis. In fact, over the last few days, some legitimate heat flux and even momentum flux has impacted the vortex, causing a split. But modeling really wants to make this "black hole-strength" mid-December; all-the-while, forecasting a mild wave 1-2 hybrid potential.

[Ji]

So this didn't workout....how accurate are these things?

they are only accurate when they show warmth. Everyime one of these shows a snow analog, it never works out

[Ji]

I had to call out Mike Masco on twitter. I like the guy and I dont want to see him become the next Justin Berk

 

https://www.facebook.com/MikeMascoMeteorologist?hc_location=timeline

[snowfan]

these guys get what they have coming to them when they start talking about epic storms on the horizon, yada yada yada.

I had to call out Mike Masco on twitter. I like the guy and I dont want to see him become the next Justin Berk

 

https://www.facebook.com/MikeMascoMeteorologist?hc_location=timeline

[WxUSAF]

Dec 2-3 is certainly a time frame that bears watching, if only because it's the next precip maker.  GFS and Euro have both trended in a way that looks a little more promising.  Cold air looks marginal though and both models are fairly light on the precip.  GEFS look good for a vort passage to our south.  

[HM]

The RNA / EPO do bring the storms and supply the cold air; but, unless we get some low anomalies to break off in SE Canada / NW Atlantic to hold confluence, we will be at the mercy of the ocean/warm air.

 

I think many will jump on these initial waves for their potential messy outcomes, esp. across the interior (hyping them beyond what they end up being). IF there is going to be any system of significance, it will be a lot later-on.

 

The anomaly pattern will be in a progressive state through mid month and then retrograde again from that point into early Jan. When you see these types of anomaly shifts and MJO progression to DL, an eyebrow gets raised. The thing keeping me from saying "significant snow," or worse, is that we have a very strong PV and lack in the NAO region. This will likely prevent something more impacting.

[usedtobe]

The GFS tonight would appear to advertise that the southern stream is not dead or dormant, it just decides to be active when it feels like it.  There is a wave that develops in the first few days of December... but it tracks off the SE coast and out to sea.  Looks like we get some kind of cutter Dec 6-7 and then maybe some wave development after that on the 8-9, but ofc, its slightly ever so warm even though there is a weak H in Quebec right where we would want it to be.

 

Out in h5 weenieland, GFS does build quite a large ridge out in the Pacific, so anything coming into the US will have to go up and over the ridge into W Canada and the Western US

 

http://mag.ncep.noaa.gov/NCOMAGWEB/appcontroller/data/gfs/00/gfs_namer_312_500_vort_ht.gif

 

Not a great pattern, but one I assume would be useful if the Atlantic decided to play nice.  At least the PV is on our side of the globe up in N Canada as well.

 

BTW, looking at Wes's weather education thread, is that a +PNA or a -PNA that the 00z GFS comes up with Days 11-15?

It's much easier to figure out with anomalies.  Here's the loading pattern for the PNA byt season.    The D+11 for doday still shows what I'd call a negative PNA but with a negative EPO because of the ridging across AK. 

 

http://www.cpc.ncep.noaa.gov/data/teledoc/pna_map.shtml

[Bob Chill]

Dec 2-3 is certainly a time frame that bears watching, if only because it's the next precip maker.  GFS and Euro have both trended in a way that looks a little more promising.  Cold air looks marginal though and both models are fairly light on the precip.  GEFS look good for a vort passage to our south.  

 

Worth watching. There's a 1030ish hp in an ok spot in se canada. No pesky gl low bringing return flow in front. GFS has a se trajectory for the vort as it approaches and exits the coast. Not unheard of but no too common either. At this point it's just a period of mild interest.

[Bob Chill]

Uncertainty with the major teleconnections remains. The bias changes daily it seems. Yesterday the gfs ens we're pointing towards a likely reloading of the AO into a solid + state after the next relaxation and the NAO was + with all member door to door. 

 

Now the members are quite mixed:

 

 

 

 

I personally think a less favorable outcome is in the cards. Models will continue to struggle with the evolution of the pv in canada. GFS hints more towards the atlantic improving than the euro. Basically, tune in tomorrow for a completely different look in the lr. 

 

It appears likely that a warmup in front of a cutter is in the cards next week. How that impacts the overall flow and what happens afterwards will be unresolved for another week. Will it be another 3 day cold spell followed by the same ole same ole or will we move towards a more favorable pattern? 

[HM]

How are the "social media giants" that like to hype model runs going to spin the 12z GFS solution which is basically zzzz....inland runners etc..... ?!?!?!?!

 

My guess: they aren't going to say anything.

 

To throw the winter fans a bone though, notice the western Pacific Jet extends and the subtropical high moves east throughout the day 3-8 period. It is at truncation that the eastward progression reverses. However, the ECMWF also stops the progression at day 8-9 too before retracting the Pac Jet. So, I'm not sure if this is related to its truncation or if it is possibly coincidence. Having said that, I think the modeling is screwing up the MJO big time.

[Ian]

i like this, too bad it's transient

 

[HM]

But Ian!!!! The WPO will save us, right?!?!

[usedtobe]

i like this, too bad it's transient

 

gfs_t2m_anomf_conus_37.png

 

 

That fits the warmer than normal Dec 5-9 above average temp idea for the southeast into our area from the D+11 centered on Dec 7.  Fits the composite pretty well. 

[HM]

That fits the warmer than normal Dec 5-9 above average temp idea for the southeast into our area from the D+11 centered on Dec 7.  Fits the composite pretty well. 

 

Impossible Wes because, as anyone who is anyone these days knows, the AO doesn't matter and the WPO will win.

[usedtobe]

Impossible Wes because, as anyone who is anyone these days knows, the AO doesn't matter and the WPO will win.

Lol,  of course it still could end up being cooler than the progs.  I know down here the AO means alot in terms of snow for a season. Years that average positive are usually not good. 

[North Balti Zen]

Nothing makes me happier than when HM, Wes, Matt and others get together to high-five over warmer temps in December...

 

yay us.

[HM]

Lol,  of course it still could end up being cooler than the progs.  I know down here the AO means alot in terms of snow for a season. Years that average positive are usually not good. 

 

Yeah, I'm being a jerk. The ridge-bridge from Siberia to Alaska is what will supply the cold into N. America. The EPO is the more direct route into the Pacific NW. Without these features, there would really be no hope or winter to talk about next month. I have just been frustrated by some people lately!

 

The thing that will help our area is if we can extend that Pacific Jet / Subtropical High eastward to the Dateline, setting up a pseudo-PNA ridge. We get really close on the modeling but then they retract it around day 8-9 or so. I think issues with tropical forcing make any solution here suspect.

[usedtobe]

Nothing makes me happier than when HM, Wes, Matt and others get together to high-five over warmer temps in December...

 

yay us.

Everybody pretty much ignores any of my posts about the possibility of there being a warm stretch or at least that is what it seems.  I'll just keep my medium range thoughts to the CWG posts and only post here if I see a real snow threat.