Winter Speculation 17/18 -December Thread

[AMZ8990]

  Looks like we have some snowpack starting to build around the globe.  Hopefully we can get some artic air moving into the area soon!

[Carvers Gap]

Dose Weeklies....wow....BN temps weeks 3-7.  Blocking up top.  Pattern shows some blocking developing from late November through much of December.  Going to pump the brakes this run as they have not been near this cold for previous runs.  Here is the snap shot of NA snow.   If those come to fruition, AMZ starts all winter threads from now on...LOL.  Look at that lake effect snow.  

[John1122]

That would definitely be an amazing start to winter. November holds the key imo. November temps seem to set up winter temps pretty nicely. Above average for November almost always ends up with warm winters, below average Novembers almost always end up with below normal winters.

[jaxjagman]

NMME went to a moderate Nina.DeJaVu 2016

 

[Carvers Gap]

8 hours ago, jaxjagman said:

NMME went to a moderate Nina.DeJaVu 2016

 

Figured.  That Niña means business.  I am rolling w the -QBO.  I might go in the ditch...but I am going to ride with it.  I do think the base pattern is slightly AN w severe cold intruding at times.  I don't think this winter will be a tame lion like last winter.  But like I always say, seasonal forecasting should never be held against a forecaster as it is almost akin to guessing.

[Carvers Gap]

Capital Wx Gang forecast for D.C.  Has some nuggets for this area as well.  Eastern forum areas will often get winter wx from storms that track to DC out of the GOM.

https://www.washingtonpost.com/news/capital-weather-gang/wp/2017/11/07/capital-weather-gang-d-c-winter-outlook-colder-and-snowier-than-last-year-but-not-extreme/?utm_term=.ed7203a220ee#comments

[AMZ8990]

  Looks like some possibilities of a nice dusting for our buddies in far north east TN.  Somewhere between the 24-26th potentially.

[BlunderStorm]

Yep, the chances are there for "something" occurring the week of Thanksgiving especially in the northern and higher elevated parts of the forum. Should things turn white I will more than happily post some pictures.  To my uneducated eye, things have seemed to be shaping up quite well in the models for the past week.

[Daniel Boone]

Some of the biggest snowstorms have occurred in late November in this area. November 25-28 1950, the great Appalachian storm, produced 17" officially at the time for Pennington gap , here in Lee County with drifts covering automobiles completely. Elevated areas of the county received even more. Pennington is at the valley floor with an elevation averaging 1400 ft. . November 1951 and 52 each recorded major snowfalls. much of ne TN and SWVA received 1-2 feet from the nov. 18, 52 storm. Also. Nov. 26, 1977 a stalled arctic frontal boundary with a wave riding along it produced 11" in Jonesville, 12" Penn. gap and 16" Big Stone Gap. KTRI received only an inch as it was mixed precip. there. There were other Nov. Snowfalls as well, Nov. '54(4"+), Nov. '71(8") and Nov. '76(3"). I'm thinking '69 had some as well but not sure. There are others of which I would have to do more research.

 

[stadiumwave]

This Nina is east based, -QBO, & low solar.  2016 was central-based +QBO...its not dejavu. 

[Carvers Gap]

37 minutes ago, stadiumwave said:

This Nina is east based, -QBO, & low solar.  2016 was central-based +QBO...its not dejavu. 

Yep.  The PDO might be a problem at some point.  I think though there are things this winter to balance out the negatives as you mention.  This winter will be a good test as several good indicators are pointing opposite directions.

[jaxjagman]

I was just pointing out what the NMME was looking like.Wasn't looking at any particulars

[jaxjagman]

1 minute ago, jaxjagman said:

I was just pointing out what the NMME was looking like.Wasn't looking at any particulars

My pic went huge for some reason

[nrgjeff]

Cold -QBO vs Nina SER engage in WWF cage match! Seriously, this weekend is a great preview of what I believe will be somewhat common. Northeast US sets record lows while the Valley gets merely brushed. Later in winter it will help NWFS though.

Unfortunately the cold pattern is likely the secondary one, with a warm dominant background possible. Still this winter should be an improvement over the last two.

[Carvers Gap]

This guy has nailed the past two winters.  Here is his forecast from the general discussion thread.  Great read and always thought provoking as he has a tendency not to get trapped by group think.

 

[John1122]

If nothing else, winters after 2020 should be normal or BN most of the time because 30 year averages will be skewed so far down. 

I hope his forecast is wrong but I wouldn't be surprised to see it correct. Still, we don't often have 3 straight uber warm years and the last two have been uber warm. But not much is normal any more.

[nrgjeff]

Isotherm has a good forecast. I am little colder but I'm still AN. For snow lovers a January 2006 would be a disaster! Long as the MJO jumps around we will have our cold periods even within a mild winter. Going optimistic, not 3 torches in a row.

[Carvers Gap]

I liked the Weeklies tonight.  Overall pattern is ridge West, trough of varying degrees in the East, and a SER battling the trough.   Blocking up top.  Overall, that look is a good one and appears stable.  The snow mean is up for the entire forum area w everybody 2"+ w eastern areas pushing 4-8" in the valleys for the 46 day period ending the first week of January.  What is encouraging is that normal temps are modeled for late Dec and early Jan.  I won't post maps this time as the Weeklies are very consistent compared to past runs.  

[Carvers Gap]

The models today seem torn....pretty much all models show a block.  Where the base of the block is positioned is at issue.   This is the 0z EPS around d14.  The bottom of the upside down omega gets pushed northeastward toward eastern Canada ever so slightly.  That allows the SER to build.  So, what normally would  be a cold pattern w a ridge out West...but in this case it  is actually warm here.  The cold settles into the northern Plains and northern Rockies.  It is not a bad pattern as the cold will have a chance to win during the middle of winter if the pattern can go that long.  The way the pattern is set-up....the cold will have a tough time holding in the West IMO.  But this is the pattern on the long range models.  The orientation of the trough is the key.  Nice +NAO there.  Nice ridge out West.  It does seem to be a pattern that will favor cutters and an occasional Nor'easter.  The Euro has a bias of holding cold in the southwest, but it is right often as well w that scenario.  So, some runs are cold and others are washed out....it is not that they models are missing the pattern, it is where that trough angle is placed.  A few degrees makes a big difference. (Edit: D'Aleo mentions a similar pattern over at WxBell.  Posted this info before seeing his.  The pattern is not the most earth shattering observation, but it is interesting.)

[Carvers Gap]

The EPS is really wanting to stick the trough back West.  Its operational seems out of sync.  The GFS and ensemble have been trending colder after several runs of a ridge in the East.  The angle of the trough is wrecking havoc....discussed above.  I really do not have a good feel for where this is headed.  The EPS is pretty solid most winters...but even it’s control run does not lock the trough West.   If pushed....would lean towards a warm start to December w a cold shot mid month of short duration...more lasting cold later in the month.  But still tough to really get a handle on the pattern as models are all over the place.  CPC shows decent teleconnection so that is a big card in our favor.  If I looked at those alone, I would say a back and forth pattern persists...Hang on tight...seems like this a winter where models may struggle.  Happy Thanksgiving to the best wx forum on the planet!

[AMZ8990]

1 hour ago, Carvers Gap said:

The EPS is really wanting to stick the trough back West.  Its operational seems out of sync.  The GFS and ensemble have been trending colder after several runs of a ridge in the East.  The angle of the trough is wrecking havoc....discussed above.  I really do not have a good feel for where this is headed.  The EPS is pretty solid most winters...but even it’s control run does not lock the trough West.   If pushed....would lean towards a warm start to December w a cold shot mid month of short duration...more lasting cold later in the month.  But still tough to really get a handle on the pattern as models are all over the place.  CPC shows decent teleconnection so that is a big card in our favor.  If I looked at those alone, I would say a back and forth pattern persists...Hang on tight...seems like this a winter where models may struggle.  Happy Thanksgiving to the best wx forum on the planet!

  When I checked this morning it looked like we could have a few days of AN temps to start December on my side of the state.  Looks like some cold air tries to push in around the 7th or 8th.  As Always, Thanks for the insight Carver. Happy Thanksgiving to you and everyone else as well!

[Carvers Gap]

AMZ...the Weeklies say, "Happy Thanksgiving, Merry Christmas, and Happy New Year!"  With the EPS being warm d10-15, I was expecting a warm run.  Weeks 3-7 feature an eastern trough.  I haven't analyzed the teleconnections other than a quick glance, but the western ridge is stout.  Week 3 kicks off the cold pattern w a -NAO and +PNA.  The NAO comes and goes from there.  The western ridge and eastern trough persists through much of the week 3 and beyond w the typical trough alignment squashing or enhancing the SER.  This run really has a cold look right before Christmas.  Check back later and I will try to add more if others have not already.   Here is the 500 pattern for wk3...you can imagine where this goes after this.  Chilly.

[AMZ8990]

6 hours ago, Carvers Gap said:

AMZ...the Weeklies say, "Happy Thanksgiving, Merry Christmas, and Happy New Year!"  With the EPS being warm d10-15, I was expecting a warm run.  Weeks 3-7 feature an eastern trough.  I haven't analyzed the teleconnections other than a quick glance, but the western ridge is stout.  Week 3 kicks off the cold pattern w a -NAO and +PNA.  The NAO comes and goes from there.  The western ridge and eastern trough persists through much of the week 3 and beyond w the typical trough alignment squashing or enhancing the SER.  This run really has a cold look right before Christmas.  Check back later and I will try to add more if others have not already.   Here is the 500 pattern for wk3...you can imagine where this goes after this.  Chilly.

That's awesome, were about due For a cooler December After the blow torches weve had the past few years. I like that -NAO as well, this should be an interesting winter!!

[Carvers Gap]

7 hours ago, AMZ8990 said:

That's awesome, were about due For a cooler December After the blow torches weve had the past few years. I like that -NAO as well, this should be an interesting winter!!

I think the first two weeks of December might be AN....what happens after that(not a sure thing) is where things might get interesting.  Certainly more to talk about than last winter where we did not have much to follow.  The Weeklies are not infallible.  But they are rarely cold in the LR for weeks at a time like they were last night.  That tells me we may be looking at a nice stretch of BN temps OR it was a hiccup by the model.  It has had blocking for multiple runs, but not every run has the same result.  The ridge out West has been a consistent feature.  The EPS yesterday on both runs all but erased that ridge.  I was surprised to see the Weeklies (based off the 0z run) take that same 0z Euro  result from yesterday (trough in West) and roll it eastward during wk 3.  I don't think it is a stretch to say it locked the cold in the East after wk3 to varying degrees.  I will have to see several runs and some OP support before buying that solution hook, line, and sinker.  The EPS yesterday was placing the trough out West in days 10-15 and showed no signs of displacement once it did so.  That gets my attention. Again, that is why I was surprised to see the cold solution for the forum area.  Sometimes that western trough takes longer to displace than the models suggest once it forms.  Maybe it is just a transitional feature.  IDK.  But that was a pretty awesome Weeklies run.  It was somewhat consistent w past runs...but somewhat in conflict w the 0z run that it was(I think) derived from.

[Carvers Gap]

12z EPS and GEFS took a step toward the Weeklies w the blocking modeled up to d10-15 and transition to an eastern trough.

[Carvers Gap]

0z EPS and 6z GEFS depict a pretty cold pattern in the LR.  500 switches around d9-10 w a transition even slightly before that.  The temps respond between d10-12. The 500 EPS maps from d11-15 are winter.  Now, let’s see if if keeps moving forward in time.  It has done that for a couple of days.  I want to see the Euro operational have it.  This is d11 on the EPS and the GEFS panel from WxBell.  As modeled(not saying this is a certainty), this matures to cross polar flow.  Both ensembles have a similar look.  Again, not the gospel but interesting.  We will see if it verifies.  Best look since the fake out last winter.

[nrgjeff]

Euro ensembles are clearly on board for the 11-15 day period. BN 500 mb anomalies are centered over the Ohio Valley, with below normal heights over our entire forum area and even points south. 850/surface temps average below normal (75%+ of members). Cold has been advertised on weeklies, so I generally trust the 11-15 day guidance.

Christmas thaw would not shock me, despite Euro weeklies keeping it cold. We'll see what they do tonight. CFS, though very late to the cold forecast, might be reasonable moderating the cold pattern toward Christmas. CFS follows recent history with a 2-week cold pattern. Case for longer duration is the triple threat blocking -AO, Alaska, and -NAO.

I would never throw around years like 2000 or 1989, back in another era when Alaska started out around -50F. AK struggles to get down to -30 these days. December 2010 might be a best case scenario including precip. December 2013 is on the other side, some cold but not all month. Either way I can't jawbone Christmas severe this year, lol!

[John1122]

Lots of chill on the GFS in the day 10-15 range as well. Hopefully some precip can line up for us over the next few weeks. It'd be nice to get some snow in the air if nothing else during December.

[Carvers Gap]

2 hours ago, John1122 said:

Lots of chill on the GFS in the day 10-15 range as well. Hopefully some precip can line up for us over the next few weeks. It'd be nice to get some snow in the air if nothing else during December.

What is up, stranger?  Been missing your input.  Pattern looks good.  EPS still on board.  

[Carvers Gap]

The Weeklies are cold and snowy.