Dec/Jan Medium/Long Range Disco

[WesternFringe]

6 minutes ago, nj2va said:

Can @pazzo83 and @WesternFringe take it to banter or just create a CC thread?  FFS.

Yeah, whatever man.  See my post.  I am not even arguing either side of cc though

my whole point is that the cavalry is late bc the model doesn’t even show what we were arguing over being impossible even happening anymore

[Jebman]

Fellow weather enthusiasts, I am so happy you are all so active on the topic, I really am. But I dont have as much time as you do. If you haven't noticed yet - Ever since I moved to Texas, my life is markedly different lol. And thats a good thing. But this topic is so active - I dont think I am gonna be able to catch up until next year lmao!

Keep up the excellent discourse! Great job!

Okay, back to Page 42.

Gotta try to catch up, gotta try to catch up, gotta try to catch up.........

[nj2va]

19 minutes ago, NorthArlington101 said:

GEFS looks slightly improved for the 2nd and 4th, FWIW. Not worth getting excited about but should reassure folks neither threat is “dead.” Also has that same window of opportunity on the 7th/8th.

Would be really funny if we did all this handwringing and somehow went on a heater.

Honestly, the GFS OP has been all over the place, even inside 120 hours, so to your point, no one should be writing things off based on OP runs.  With so many vorts, I have a feeling we’ll be having things pop up in the medium term vs long lead threats - unless we get some insane blocking thanks to our (now cancelled?) SSW.  

[Jebman]

On 12/25/2023 at 10:12 AM, Kevin Reilly said:

I will take 1996 and 2010 for $1,000 Alex!

You just won that question TWICE!

DC gets twice as much snow as they got in both those years, in one incredible winter!

[Weather Will]

In an attempt to lighten the mood, fantasy range WB GFS 18Z northern plains windchills, first time I have seen this in forever....hint of things to come?????

[Stormchaserchuck1]

28 minutes ago, Weather Will said:

In an attempt to lighten the mood, fantasy range WB GFS 18Z northern plains windchills, first time I have seen this in forever....hint of things to come?????

578dm -NAO and 554dm -EPO.. pretty good run @384. I think they are really anticipating Stratosphere warming: It has +3 correlation on NAO at +0D but +10 correlation at +20-30 day. But even so, the last 3 Stratosphere warmings have effected us when the Pacific also became unfavorable (so negatively) so it should be interesting 

[Stormchaserchuck1]

2 hours ago, EastTNWeatherAdmirer said:

Who knows if the JMA is even worth checking out and I wish I could see the surface precip with it, but it shows a significant storm for Jan 2nd over the mid Atlantic.

It has literally never gotten one right when against other models. 

[WxUSAF]

Good thread from Tomer tonight 

 

[BristowWx]

33 minutes ago, Weather Will said:

In an attempt to lighten the mood, fantasy range WB GFS 18Z northern plains windchills, first time I have seen this in forever....hint of things to come?????

Interesting the lowest wind chill on that scale is -100.   How often does that happen?  

[cbmclean]

12 minutes ago, BristowWx said:

Interesting the lowest wind chill on that scale is -100.   How often does that happen?  

I suspect very, very rarely anywhere outside of Antarctica.  Here is a copy of the "official" chart from WEATHER.GOV.  You'd have to have below -45 F with > 60 mph winds.

 

 

[cbmclean]

54 minutes ago, Weather Will said:

In an attempt to lighten the mood, fantasy range WB GFS 18Z northern plains windchills, first time I have seen this in forever....hint of things to come?????

I think we've been kind of blocking it out because we've been wallowing in the misery of an endless SE ridge, but flyover country has had several notable cold outbreaks over the last few years.  So it can still get cold, there at least.

Here's the on that almost brought modern civilization to its knees in Texas.

https://en.wikipedia.org/wiki/February_2021_North_American_cold_wave

[Eskimo Joe]

2 hours ago, NorthArlington101 said:

GEFS looks slightly improved for the 2nd and 4th, FWIW. Not worth getting excited about but should reassure folks neither threat is “dead.” Also has that same window of opportunity on the 7th/8th.

Would be really funny if we did all this handwringing and somehow went on a heater.

I'm all for that. I'm legit hoping we got bonkers January and February and March, but man it's hard to bet against the house these days.

[RDM]

34 minutes ago, cbmclean said:

I suspect very, very rarely anywhere outside of Antarctica.  Here is a copy of the "official" chart from WEATHER.GOV.  You'd have to have below -45 F with > 60 mph winds.

 

 

A bit off topic, but we were off the lower end of the chart in Ohio during the blizzard of 78.  Wind chill was -60+.  Mainly due to the winds (70+ mph gusts with sustained over 50).  The temps were down below zero too, after being in the upper 40's the evening before.  The 24 hour temperature drop was one of the largest ever recorded for Ohio.  Over 50 lost their lives - mainly due to the white out conditions and freezing to death.  Nrn Ohio and Michigan got the worst of it where the flat terrain offered little resistance to the wind. 

Was 16 at the time and will never forget the sound of the howling winds, which started very early on the morning the storm hit.  The howled all day and into the morning of the second day.  Farmers lost an untold number of livestock, despite efforts by the National Guard who delivered feed by helicopter.  Many roads around our town north of Dayton were closed for more than a week until they brought out the snowblowers from Dayton Airport and Wright Patterson AFB.  Was an amazing experience.  

[Eskimo Joe]

 

 

[TSSN+]

20 minutes ago, Eskimo Joe said:

 

 

Aka nothing yields a snowy pattern or all about timing and luck. 

[snowfan]

1 hour ago, BristowWx said:

Interesting the lowest wind chill on that scale is -100.   How often does that happen?  

Not often. It’s rare. Last winter, Mt Washington in NH recorded a wind chill below -108 F. The air temp was -47 F with winds over 100mph. 

[Dan76]

[NorthArlington101]

I guess I wouldn’t bet my life this wouldn’t happen, but it’s concerning how bad the gfs is 4 days out.

[Heisy]

End of cmc run looks juicy. Probably need a little movement in key pieces, but it’s close. I personally like 6-8th as the time frame to watch


.

[high risk]

6 hours ago, pazzo83 said:

i don't think you are quite grasping what he's saying.  all weather models are probabilistic models that factor in historical data, current observed data, and the understood mathematics that describe the atmosphere.  obviously it could be wrong because models are often wrong.  but let's look at the inputs again - unless you are arguing that one of those inputs was somehow corrupted for this particular model run, it is telling you that the most likely outcome is what is shown (with rain basically everywhere).  i think that is where the concern lies - it is outputting an outcome that is not what one would've expected in years past, meaning it is incorporating some sort of fundamental change in terms of those inputs.  I don't think the math has changed wildly (if only to improve model precision), so...

         This isn't how standard NWP works.    Historical data plays no role:   you have equations that represent all relevant processes, you create an initial state based on observations, and you integrate the model.     Historical data *does* factor in for AI/ML approaches, but if you're just looking at a standard GFS forecast map, it doesn't know anything about years past.

     

[WEATHER53]

Last times DCA had 6”+ in Dec was 2009, 1983, 1973, 1969. 

[Jebman]

4 hours ago, cbmclean said:

I suspect very, very rarely anywhere outside of Antarctica.  Here is a copy of the "official" chart from WEATHER.GOV.  You'd have to have below -45 F with > 60 mph winds.

 

 

That would be a truly spectacular jebwalk!

[jayyy]

Last times DCA had 6”+ in Dec was 2009, 1983, 1973, 1969. 

4 times in 54 years and folks are saying “iDK mAn… ItLL nEvER sN0w aGaIn cUz iT hAZnT sn0wed bY JaN 2nD”

It can still get quite cold at our latitude, we can still get snow, and we can still see heater winters. Calm the fuck down yall. Our day will come.

[Ji]

Some how the 4th 5th wave on euro is rain....but d10 looks good for a snowy setup

Sent from my SM-A515U using Tapatalk

[Jebman]

1 hour ago, jayyy said:

4 times in 54 years and folks are saying “iDK mAn… ItLL nEvER sN0w aGaIn cUz iT hAZnT sn0wed bY JaN 2nD”

It can still get quite cold at our latitude, we can still get snow, and we can still see heater winters. Calm the fuck down yall. Our day will come.

LOL LMAO

[CAPE]

The shortwave energy in the southern stream flow looks healthy for the 4-5th window. Need to watch the timing of NS energy dropping southward to see what influence it may have. This period still seems like the first legitimate chance for something with some decent cold available.

[CAPE]

Next up- There is an indication of a wave tracking across the Gulf states for the 7-8th.

Pretty far out, but there is an indication of another storm around the 11th as energy drops southeastward ahead of a developing ridge off the west coast. It shouldn't be boring over the next couple weeks. Impressive -NAO signal on the means.

 

[jayyy]

Next up- There is an indication of a wave tracking across the Gulf states for the 7-8th.

Pretty far out, but there is an indication of another storm around the 11th as energy drops southeastward ahead of a developing ridge off the west coast. It shouldn't be boring over the next couple weeks. Impressive -NAO signal on the means.

 

The chances should to be plentiful over the next several weeks. Thank you niño! Said this the other day, but IMO, the most likely way to maximize snowfall potential from these 3 setups is if storm #1 (4-5th) ends up being the “setup storm” for the trailing 1 or 2 shortwaves. Historically it would be the least impactful, coming at the beginning of train tracks pattern with a marginal (but workable) airmass, but could also prove to be the most important wave, as it would lay the groundwork for a better h5 look once the 7th rolls around ie: ushering in legitimate cold air, laying down some snowpack to our north, and by potentially slowing down the flow upstream a bit, allowing storm #2 to potentially slow down and go boom.

All speculation of course and I’m just thinking out loud here, but if we could manage to get even a little bit of snow from wave 1 and then cash in on at least one of the following two, that’d be a great way to kick off the new year. It’d certainly help get weenies off the proverbial ledge.

[CAPE]

3 minutes ago, jayyy said:

The chances should to be plentiful over the next several weeks. Thank you niño! Said this the other day, but IMO, the most likely way to maximize snowfall potential from these 3 setups is if storm #1 (4-5th) ends up being the “setup storm” for the trailing 1 or 2 shortwaves. Historically it would be the least impactful, coming at the beginning of train tracks pattern with a marginal airmass, but could also prove to be the most important wave, as it would lay the groundwork for a better h5 look once the 7th rolls around ie: ushering in legitimate cold air, laying down some snowpack to our north, and by potentially slowing down the flow upstream a bit, allowing storm #2 to potentially slow down and go boom.

All speculation of course and I’m just thinking out loud here, but if we could manage to get even a little bit of snow from wave 1 and then cash in on at least one of the following two, that’d be a helluva way to kick off the new year.

This process is how it works in many cases, and in particular when there isn't an existing block in place.

[jayyy]

This process is how it works in many cases, and in particular when there isn't an existing block in place.

Right on. I envision each passing wave acting as a bootleg 50/50 for the following wave in that it would slow things down upstream just enough to allow things to potentially come together 3-4 days later.

Going to be a very interesting next 5-7+ days of model runs.