2015-16 Winter Pattern Discussion

[Iceagewhereartthou]

The cool down to me looks unimpressive next week, at least it will be near normal. Then looks like we semi warm up again per 6z GFS. YUK

Taken at face value I would agree, close to normal is not particularly exciting, and will not deliver the fun stuff to almost any of us. But as others have said, normal is way better than where we have been and so it is an important first step. If we see that it quickly reverts back to torch like what we saw with last week's cool down, then I would be more concerned. That is what happened the entire winter in 2012-2013, quick cool downs to normal then right back up. Fortunately, our pattern does not seem to be headed that way. For now, I'll just be happy to need long sleeves and a jacket in the morning.

[snowlover91]

Taken at face value I would agree, close to normal is not particularly exciting, and will not deliver the fun stuff to almost any of us. But as others have said, normal is way better than where we have been and so it is an important first step. If we see that it quickly reverts back to torch like what we saw with last week's cool down, then I would be more concerned. That is what happened the entire winter in 2012-2013, quick cool downs to normal then right back up. Fortunately, our pattern does not seem to be headed that way. For now, I'll just be happy to need long sleeves and a jacket in the morning.

More than likely it was just another crazy GFS run. The GEFS ensembles actually trended better, 00z GFS went back to much colder extended range, the Euro and its ensembles also indicate a good pattern through 240 and the CMC ensembles have a super blocking pattern in their long range. Overall when I see one model run go against every other model and ensemble, and it's next run 6 hours later flips to what other models are showing, it tells me that run doesn't have much going for it.

The big news I see is D10 on Euro it finally shows the PV splitting at the 50hpa level. This is the first time I've seen the Euro protecting this at any level and is encouraging. I think we have a great chance at seeing a SSW in mid January, with the winter of 1957-58 as my top analog for this year and the PV similarities. That year featured a SSW on the 30th and this year has many similarities to that one in regards to PV strength and positioning. If this indeed does occur as modeled the Euro and GFS indicate half moving towards the Hudson Bay Area and the other going for Siberia. Now we just have to wait and see what happens.

Regarding the Nino pattern, there are stretches where it may be dry for a week but then once the moisture returns it's usually wet for days at a time. RDU is averaging almost 12" above average this year and some places in Eastern NC are 15-20" above average. Models also struggle during pattern changes and sometimes you have systems suddenly pop up 3-5 days out on them, a strong possibility the first week of January.

[packfan98]

Does anybody else like this look on the 06z GFS?

[FallsLake]

Does anybody else like this look on the 06z GFS?

Verbatim it is a great track. But of  course way out in the fantasy time period. It is good to see the pattern being depicted. 

[weathertree4u]

Verbatim it is a great track. But of  course way out in the fantasy time period. It is good to see the pattern being depicted. 

Yea, looks great to me, I am north of Nashville so bring it on!

[packbacker]

One of the biggest end of month flips for the CFS that I can recall.  These are the last 3 runs for January...amazing cold being shown, very Jamstec'ish.  Of course we got 4 more runs left so it could flip back.

 

 

[packbacker]

Days 6-10 obviously look dry but days 10+ it looks to be atleast a little more active, with the blocking being show and and what should be a suppressed storm track...

 

See so-Cali getting in on the action too...#STJFinally?

[Jonathan]

One of the biggest end of month flips for the CFS that I can recall. These are the last 3 runs for January...amazing cold being shown, very Jamstec'ish. Of course we got 4 more runs left so it could flip back.

What a coup for the Jamstec model if that ends up verifying. That'd be a big confidence boost in a relatively unheard of climate model going forward.

[Brick Tamland]

Regarding the Nino pattern, there are stretches where it may be dry for a week but then once the moisture returns it's usually wet for days at a time. RDU is averaging almost 12" above average this year and some places in Eastern NC are 15-20" above average. Models also struggle during pattern changes and sometimes you have systems suddenly pop up 3-5 days out on them, a strong possibility the first week of January.

That is something I have noticed regarding the precip. Ever since the start of fall, when we do get precip it usually hangs around for two or three days instead of just coming in and moving out in a day. All we need is that to keep up with the cold air around. And it doesn't have to be bitter cold, just cold enough for snow.

WxSouth also said he would not be surprised to see systems pop up on the models two to three days out. It actually sounded like he expected that to happen this winter.

[Jonesing for a chase]

6Z also advertising a low after truncation that skims outer banks. Plenty of time to trend NW. Also do I see a big H sitting in Greenland the last 2 runs? Would be nice.

[griteater]

One of the biggest end of month flips for the CFS that I can recall. These are the last 3 runs for January...amazing cold being shown, very Jamstec'ish. Of course we got 4 more runs left so it could flip back.

Pack that's a crazy flip for the CFS if it holds

[Jon]

One of the biggest end of month flips for the CFS that I can recall. These are the last 3 runs for January...amazing cold being shown, very Jamstec'ish. Of course we got 4 more runs left so it could flip back.

Once the CFSv2 started advertising a deep -AO/-NAO/+PNA it was only a matter of time. Didn't expect that kind of cold though overall.

Nice flip indeed.

[stadiumwave]

Uh oh....CFS v.2 got the memo that winter is coming....LMBO:












Question is....will all the warm weenies who've  tortured winter weather lovers with CFS image keep posting & tweeting them now. :) :)

[Cold Rain]

That is exactly the point I was making above. A warm December is fine. But the background state of the atmosphere is starting to get worrisome. As I said the other day, we're going to know some things about January very soon now.

This post was referencing an earlier one that essentially opined that if we were salvage January, we needed to start seeing some positive steps soon. And boy have we! It now seems likely that from mid-January on winter will finally be around in the east. It's good to see the CFS turn around as well as see the Strat PV get disturbed. This process, should it come to pass, validates the analogs and some of the seasonal models, which I am happy to see.

[Wow]

6z GFS looks like a winner - Jan 4 threat of a snow event from a piece of energy dropping down from the northern jet and pops a low off the coast & throws some light snow back.  Then as the pattern continues to unfold with blocking building over the Arctic, the PV drops south and the PNA ridge spikes to pop a Miller A storm over the GOM.

 

Beyond there, the AK block strengthens and moves over the pole and further displaces the PV & puts us into the freezer.  Whatever snow is on the ground would be sticking around a while.

[downeastnc]

Just need this 150 miles or so further west

 

[packbacker]

This post was referencing an earlier one that essentially opined that if we were salvage January, we needed to start seeing some positive steps soon. And boy have we! It now seems likely that from mid-January on winter will finally be around in the east. It's good to see the CFS turn around as well as see the Strat PV get disturbed. This process, should it come to pass, validates the analogs and some of the seasonal models, which I am happy to see.

 

I was hoping we would start seeing the strat response around Xmas which would translate to a flip around mid-month.  Obviously the models are going gung ho with blocking the first week of Jan so that is somewhat of a surprise.  But, still think it will be mid-month, at the earliest, before we start seeing a consistent plains to SE trough.  If, and still a big IF, we do get a SSWE in mid-Jan then we won't know how things will shake out for end of Jan into Feb for couple of more weeks.  Not ready to spike the football on a SSWE yet.

 

Something has to give with what the models are spitting out...with a +PNA/-EPO/-AO that shouldn't translate to a SW trough.  That little low up in Hudson Bay needs to get out of there so maybe that's whats causing higher heights in east in the long range.

[No snow for you]

The teleconnections still look great. The euro has the AO going negative on Jan 1 and at the end of the run at -3.5. The NAO goes negative also on Jan 1 and drops to -2 by the end of the run. The PNA goes positive on the 29th and goes +3.5 before coming back to +2.5 by the end of the run. The EPO doesn't go crazy negative like previous runs but still goes negative on the 29th and hangs around -1. I can't remember the last time we had everything going our way in this area.

[packbacker]

End of the EPS and GEFS to some extent are lowering heights in the east at the end of it's run and see plains trough, so looking towards mid-month hopefully we see something settled in...

[Brick Tamland]

The teleconnections still look great. The euro has the AO going negative on Jan 1 and at the end of the run at -3.5. The NAO goes negative also on Jan 1 and drops to -2 by the end of the run. The PNA goes positive on the 29th and goes +3.5 before coming back to +2.5 by the end of the run. The EPO doesn't go crazy negative like previous runs but still goes negative on the 29th and hangs around -1. I can't remember the last time we had everything going our way in this area.

Not aure of the last time, but anytime we have had these combos in the past it has resulted in a lot of snow for the Carolinas.

[packbacker]

Posted this a few days back I think, but these are all the mod+ nino's with strong ridging  in NW Canada, B/K high...if those persist then we should see a plains to SE trough soon, mid-Jan is my guess, unless ridging shifts towards Hudson Bay...

[CAD_Wedge_NC]

The teleconnections still look great. The euro has the AO going negative on Jan 1 and at the end of the run at -3.5. The NAO goes negative also on Jan 1 and drops to -2 by the end of the run. The PNA goes positive on the 29th and goes +3.5 before coming back to +2.5 by the end of the run. The EPO doesn't go crazy negative like previous runs but still goes negative on the 29th and hangs around -1. I can't remember the last time we had everything going our way in this area.

With all the indices forecast to be favorable, and if the PV splits, we could be looking at a super cold outbreak at some point. This reminds me of Jan 1985 in many ways. Hold onto your hats folks. It's going to be a wild ride, if this comes to pass.

[Bhs1975]

With the bath water just offshore bombogenesis potential is high.

[Jon]

Posted this a few days back I think, but these are all the mod+ nino's with strong ridging in NW Canada, B/K high...if those persist then we should see a plains to SE trough soon, mid-Jan is my guess, unless ridging shifts towards Hudson Bay...

HM via Twitter "The prospects for a 1958 or 1983 like ending in the eastern US have significantly increased in probability. But what form does 2016 take?"

I'll take an averaged form of the two...

[cbmclean]

As if in answer to my question, I found this interesting article on FiveThirtyEight.com

Forgot the link

 

http://fivethirtyeight.com/features/whats-causing-this-warm-christmas-in-the-eastern-u-s/

[FallsLake]

Bad run of the 12z GFS. I would guess in the medium range there could be some hope for something wintery; but in the LR there would be no real push of cold air into the SE. Do I believe it, not really. I suppose its possible but with all the good signs of blocking you have to figure more cold air will get pushed southward.

[mackerel_sky]

Bad run of the 12z GFS. I would guess in the medium range there could be some hope for something wintery; but in the LR there would be no real push of cold air into the SE. Do I believe it, not really. I suppose its possible but with all the good signs of blocking you have to figure more cold air will get pushed southward.

6z was ugly too! A bad trend

[BullCityWx]

6z was ugly too! A bad trend

No it wasn't. There was a nice snow event on the 6z for many areas.

http://68.226.77.253/text/offhrGFSxExtract/GFS_KAKH.txt

[WXinCanton]

Bad run of the 12z GFS. I would guess in the medium range there could be some hope for something wintery; but in the LR there would be no real push of cold air into the SE. Do I believe it, not really. I suppose its possible but with all the good signs of blocking you have to figure more cold air will get pushed southward.

 

using the OP for long range is usually pretty fruitless IMO

[snowlover91]

HM via Twitter "The prospects for a 1958 or 1983 like ending in the eastern US have significantly increased in probability. But what form does 2016 take?"

I'll take an averaged form of the two...

In my post a few pages back those were my top two analogs for how I expect January and February to unfold. If you look at the reanalysis maps for the PV in 57-58, it was remarkably similar in size, strength and positioning to what we saw in December. The breakdown of it in January is also similar to what the models show in the short range with warming in the exact same region. That year saw an SSW on January 30th. January was below average and February was a freezer. The year of 82-83 had a torch December like we saw and below average across the SE states with blocking into central and western Canada. If you blend those two together you get a below average January and a frigid February, which is how I expect the winter to unfold.

I'm still waiting for those who said awhile back that the pattern change wasn't coming, we would torch all winter, and that the early January flip I was predicting wouldn't verify because the models would push it back till February..