December 2017 Mid-Long Range Disco 2

[showmethesnow]

Just now, Rtd208 said:

I honestly would rather have a storm a day or two after Christmas rather then on Christmas itself since that could really throw a wrench into alot of peoples plans including mine. Hopefully the models will keep trending in the direction of increasing the winter storm potential in the timeframe you mentioned above. Good write up.

I have never been overly high on the pre Christmas/Christmas time period. Thought things were being rushed a little on the models. But you never know. My expectations have been more on the time period immediately after Christmas and running for an extended period of time beyond that. Potentially very extended at that. Guess we will see. 

[showmethesnow]

Just now, losetoa6 said:

Another real nice writup @showmethesnow. You got a real sharp eye and nose . Keep it up 

Thank you. Meant to ask you the other day. How was the Last Jedi? Kids enjoy it? Probably go see it myself over the Holidays.

[showmethesnow]

The 06Z GEFS is very quick with the cold. Not dumping the trough surge coming out of Canada into the Southwest instead it is dumping it straight down and east. Getting the cold into our region early on Sunday. 

[Interstate]

so the Euro still puts us around 70 Christmas day.  I would take that if it gives us cold and storm leading up to NYE

[aldie 22]

7 minutes ago, showmethesnow said:

The 06Z GEFS is very quick with the cold. Not dumping the trough surge coming out of Canada into the Southwest instead it is dumping it straight down and east. Getting the cold into our region early on Sunday. 

Must be wrong didn't yesterday's ensembles say differently? Or are the ensembles only as good as the next run? Asking for a friend

[BristowWx]

6 minutes ago, showmethesnow said:

The 06Z GEFS is very quick with the cold. Not dumping the trough surge coming out of Canada into the Southwest instead it is dumping it straight down and east. Getting the cold into our region early on Sunday. 

Do you believe it?  I mean there are two scenarios.  Dump the trough in the SW and its warm...don't and its colder faster.  Euro seemed to still like the SW dump.  but then I hear that it likes to do that but I am not sure that holds water.  we are getting to the time where op runs have some merit.  maybe somewhere in the middle.  the change on the GFS from 18z is quite impressive

[showmethesnow]

9 minutes ago, leesburg 04 said:

Must be wrong didn't yesterday's ensembles say differently? Or are the ensembles only as good as the next run? Asking for a friend

That's why I have to laugh when people live and die with each run of the models (took me years and years of heart ache not to do this myself). Saw yesterdays runs and I just knew there were meltdowns a plenty. Have said this time and again but this probably won't be resolved on the models until shortly before the trough starts surging out of Canada. Until then we are probably going to see the models all over the place.

9 minutes ago, BristowWx said:

Do you believe it?  I mean there are two scenarios.  Dump the trough in the SW and its warm...don't and its colder faster.  Euro seemed to still like the SW dump.  but then I hear that it likes to do that but I am not sure that holds water.  we are getting to the time where op runs have some merit.  maybe somewhere in the middle.  the change on the GFS from 18z is quite impressive

Not sure really what to expect. Probably be a compromise where some of the trough energy gets dumped into the southwest and some is free to move east. I still think at this point we are probably looking at the cold for our region later in the Christmas period rather then sooner. But I wouldn't put money on that.

[BristowWx]

2 minutes ago, showmethesnow said:

That's why I have to laugh when people live and die with each run of the models (took me years and years of heart ache not to do this myself). Saw yesterdays runs and I just knew there were meltdowns a plenty. Have said this time and again but this probably won't be resolved on the models until shortly before the trough starts surging out of Canada. Until then we are probably going to see the models all over the place.

Not sure really what to expect. Probably be a compromise where some of the trough energy gets dumped into the southwest and some is free to move east. I still think at this point we are probably looking at the cold for our region later in the Christmas period rather then sooner. But I wouldn't put money on that.

Thanks...I melted down for sure.  I became overwhelmed thinking about opening windows and wearing shorts and visions of last Dec were dancing in my head.  both GEFS and I think EPS show cold coming in regardless...GEFS sooner than EPS..I can live with that

[Ralph Wiggum]

Do you believe it?  I mean there are two scenarios.  Dump the trough in the SW and its warm...don't and its colder faster.  Euro seemed to still like the SW dump.  but then I hear that it likes to do that but I am not sure that holds water.  we are getting to the time where op runs have some merit.  maybe somewhere in the middle.  the change on the GFS from 18z is quite impressive

GFS family has been bouncier than a super ball filled with jumping beans riding a pogo stick on a trampoline. Might have merit but I would side with consistency. EPS/GEPS have been rather steady.

[showmethesnow]

9 minutes ago, Ralph Wiggum said:

59 minutes ago, BristowWx said:

Do you believe it?  I mean there are two scenarios.  Dump the trough in the SW and its warm...don't and its colder faster.  Euro seemed to still like the SW dump.  but then I hear that it likes to do that but I am not sure that holds water.  we are getting to the time where op runs have some merit.  maybe somewhere in the middle.  the change on the GFS from 18z is quite impressive

GFS family has been bouncier than a super ball filled with jumping beans riding a pogo stick on a trampoline. Might have merit but I would side with consistency. EPS/GEPS have been rather steady.

Until the last day or so of runs I thought the GEFS was more consistent vs the EPS which was a little more jumpy. But I was focusing on the SW trough so maybe in other areas the EPS was doing a better job.

eta: Thinking about it, I wasn't really focusing on the pre-Christmas time period as much as on the whole run in its entirety which GEFS was very consistent with. So maybe the EPS was doing a better job with that feature before Christmas and I just didn't realize it.

[Ralph Wiggum]

Until the last day or so of runs I thought the GEFS was more consistent vs the EPS which was a little more jumpy. But I was focusing on the SW trough so maybe in other areas the EPS was doing a better job.

I also notice the GFS has tended to go more progressive with certain H5 features in the MR only to trend slower as lead time shortens. Not sure if this is something to do with the old GFS over-amplification biases and the update to fix this when the para took over, but something that has stood out to me anyway. Not saying the GFS colder Christmas solutions cant verify, I would just take with many grains of salt until there is some support.

[Ralph Wiggum]

NAVGEM ticked North again with Wed PM precip. Gets moisture into parts of the region. As far as trof boundary getting S and E for Christmas, NAVGEM much slower and less progressive than GFS. Clues from this model telling me the boundary passage is going to be delayed.

[Z-Cast]

GFS seemingly always too progressive with fronts. Buyer beware with the speed of cold air via 06z.

[AfewUniversesBelowNormal]

Look what finally showed up on GFS ensembles, coldest air in a long time. 

 

[AfewUniversesBelowNormal]

It's gone pretty fast though. 
 

upload picture

[BristowWx]

38 minutes ago, Z-Cast said:

GFS seemingly always too progressive with fronts. Buyer beware with the speed of cold air via 06z.

Somewhere in between might be good though.  

[frd]

2 hours ago, showmethesnow said:

I have never been overly high on the pre Christmas/Christmas time period. Thought things were being rushed a little on the models. But you never know. My expectations have been more on the time period immediately after Christmas and running for an extended period of time beyond that. Potentially very extended at that. Guess we will see. 

I totally agree, signs of an active Southern stream and  White New Years is on the table.

Cold air I believe is still being underforecasted by the models and I look foward to additional positive changes in the days ahead for our region. 

I agree as well, a battle zone near our area later in the month, plus we have the crazy area of + Atlantic SSTs.

Meanwhile, still favorable Pac forcing / MJO ( maybe even a MJO lag as well can be anticipated )  and help from the strat next week and continuing to month's end.      

Maybe something big later in the month. 

From Jason 

 

 

 

[BristowWx]

45 minutes ago, Z-Cast said:

GFS seemingly always too progressive with fronts. Buyer beware with the speed of cold air via 06z.

And 0z GFS.  not as fast but fast enough.  EPS was also faster just not as fast.  Euro Op was not. we'll know something next Monday or so.

[Ralph Wiggum]

EPS upon further inspection not *horrible* but still not quite a snowy looking map for the holiday like the 0Z GFS op had verbatim. However, notable changes as the boundary is a shade quicker moving thru. Probably in actuality need this feature about 12-18 hours faster if hoping for holiday cold but a step towards the good and still about a week out. You can see on the 2m means the cold air seeing into the region during the day on the 25th. Surface slp maps on the EPS mean still showing sprawling HP seeping across the Northern part of the country and headed East. Also of note is the persistent (and increasing?) signal on the EPS for a wave along the Gulf Stream on Christmas. Now whether this is just the front passing thru, an actual wave of LP, or cold chasing the precip is up for discussion. I will say tho, finally seeing a closed off circulation off the coast is not a bad signal at this range on a means and worth keeping one eye open towards:

eta: some guidance is close to having a quasi 50/50 low as well and you can see that feature here tho displaced....but not impossibly far off.

[MN Transplant]

9 hours ago, Cobalt said:

 

 

Bastardi is reaching here.  The 1996 outbreak was historic and included a closed -40C 850 contour over northeast MN, where the all-time record low for the state was set.  This is a nice progged outbreak, but not in the same ballpark.

The other thing about '96 was that while it was colder than '94 in MN, it didn't translate as far S & E.  DCA's coldest day was 17/9 in 1996 vs 8/-4 in 1994. 

[WxUSAF]

 

[Bob Chill]

Jan 94 put together the perfect package to push the core of the cold well south of the US/CN border. Similar pna/epo ridge config to what seems to be on the way but also a large blocking upper level ridge basically parked over the pole and some nao help as well. This pushed the core of the trop PV into the conus.

We don't have a block over the pole showing up but we do have a good trough axis+cross polar flow. It's likely that cold will be invading the US but prob at least several magnitudes less than what happened in 94. If the EPO ridge folds over an closes off over or near the pole then things could get interesting. Not seeing that happening on anything attm. 

 

[Bob Chill]

If you look at the gefs 5 day mean, it does look a little like the Jan 94 setup minus the block over the pole. Some hints of the EPO ridging folding over but the trop pv isn't nearly as displaced as 94.

 

Not a bad panel here for cold in the US though. Should be some interesting weather coming up for a lot of people. This mean would still deliver plenty of cold and plenty of sub zero stuff in the upper MW. 

[clskinsfan]

You have to love the look of a very active southern stream that the models have been spitting out. And it seems like that southern stream activity will remain right into mid January. There is no guarantee that track/cold will work out. But I would love to take my chances with an active southern stream while heading into our best climo period.

[usedtobe]

13 minutes ago, WxUSAF said:

 

Good post.  The Euro ensembles certainly show lots of uncertainty looking at the spaghetti plots and it makes sense that the west ridging would be less diggy towards the west and therefore faster getting the front to the east coast.

[Bob Chill]

9 minutes ago, usedtobe said:

Good post.  The Euro ensembles certainly show lots of uncertainty looking at the spaghetti plots and it makes sense that the west ridging would be less diggy towards the west and therefore faster getting the front to the east coast.

Majority of guidance moved things along since rock bottom 12z yesterday. If those runs mark the worst case scenario, I think we can all relax a little and not worry so much. The big dig into the west idea is losing steam fast. Now we need to work on the SE ridge helping instead of hurting. 

[clskinsfan]

12Z 3K NAM is close to getting precip into the area for the Wednesday night/Thursday event. It is at the end of the run. But something to watch at least.

[yoda]

06z GFS was pretty nice at the extended... two nice chances of frozen/snow

[PDIII]

4 hours ago, Rtd208 said:

I honestly would rather have a storm a day or two after Christmas rather then on Christmas itself since that could really throw a wrench into alot of peoples plans including mine. Hopefully the models will keep trending in the direction of increasing the winter storm potential in the timeframe you mentioned above. Good write up.

This kind of talk is only acceptable in the banter thread...  And imho has no place on americanwx. 

Sorry but this is just how I feel.

 

[WinterWxLuvr]

Just now, PDIII said:

This kind of talk is only acceptable in the banter thread...  And imho has no place on americanwx. 

Sorry but this is just how I feel.

 

Your post is worse.