cbmclean

15 minutes ago, CAPE said:

It might be interesting/useful for you to create an h5 anomaly plot for each of those Decembers individually.

I'm at the inlaws for Xmas so hopefully I'll have some time to play this evening

15 minutes ago, CAPE said:

That is a multiple year monthly composite mean at h5 for December. There would have to be some amount of ridging in the Western US (during Dec) for at least parts of some of those years. When presented as a multi-year composite, the height anomalies there are less prominent and get 'washed out'.

True, but there is the strong eastern trough signal as well as a weaker but less robust trough off the west coast.  I'm just surprised to not see a similar consistent signal in the western conus.  The patterns are complex and many-faceted, and sometimes defy easy characterization

54 minutes ago, CAPE said:

That is the typical -NAO dipole look. When there are anomalous +heights over the NA, the heights adjacent to it are anomalously low. The oddity is the ridging that has been occurring underneath lately despite that. It is what you would generally expect if the NAO were significantly positive(lower h5 heights over GL).

eta: a super -PNA can certainly overwhelm a weaker/east based -NAO, but typically if the NAO is legit negative, SE ridge is suppressed.

I was more referring to the lack of positive anomalies in the western CONUS.  Surprised to see that with troughing to the east and the west.

ETA: I am referring to the bottom composite.

1 hour ago, Maestrobjwa said:

Thought this was a relevant nugget

 

Also interesting that the WAR doesn't show up on this year.  It just appeared when it counted I guess.

1 hour ago, Maestrobjwa said:

Thought this was a relevant nugget

 

Interesting that the strong troughs in the east in the bottom pic are not reflected by a strong ridge in the west.  How is that possible?

13 minutes ago, high risk said:

     I should have clarified that the model struggles with the temperature drop were east of the mountains.... which makes sense.

Every model in history has overestimated the speed of cold air going through the mountains.  It's just something that has to be manually corrected for.  Not sure why they can't get those physics right.  But overall this front seems to have been well-modeled from range.

26 minutes ago, Maestrobjwa said:

Same! Yeah sometimes I wish he wouldn't to keep things lighter at least for this time of year...BUT, a stat is still a stat and doesn't quite care how it makes ya feel, lol

The truth shall set us free...free of snow.

6 minutes ago, cbmclean said:

Definite retrograding of the AK vortex.  Lets hope this look continues to move forward in time.

Anyone with access to the long range EPS, is it showing similar hope, or is it to depressing to even mention?

4 hours ago, CAPE said:

Marked improvement in the advertised h5 pattern towards the end of the 0z GEFS, especially out west. Hopefully the reshuffle/mild period lasts only about a week.

Definite retrograding of the AK vortex.  Lets hope this look continues to move forward in time.

Looking at the TNH temp correlation, there doesn't seem to be much for the eastern seaboard.  Is it something that affects snowfall more than average temperature here?

Not very familiar with the TNH teleconnection.  Reading up on it a bit at the CPC site.  From their write-up its not really clear which phase is better for the eastern CONUS.

From https://www.cpc.ncep.noaa.gov/data/teledoc/tnh.shtml

The positive phase of the TNH pattern is associated with below-average surface temperatures throughout the western and central United States, and across central and eastern Canada. It is also associated with above-average precipitation across the central and eastern subtropical North Pacific, and below-average precipitation in the western United States and across Cuba, the Bahama Islands, and much of the central North Atlantic Ocean.

The negative phase of the TNH pattern is often observed during December and January when Pacific warm (ENSO) episode conditions are present (Barnston et al. 1991). One recent example of this is the 1994/95 winter season, when mature Pacific warm episode conditions and a strong negative phase of the TNH pattern were present. During this period, the mean Hudson Bay trough was much weaker than normal and shifted northeastward toward the Labrador Sea. Additionally, the Pacific jet stream was much stronger than normal and shifted southward to central California, well south of its climatological mean position in the Pacific Northwest. This flow pattern brought well above-normal temperatures to eastern North America and above-normal rainfall to the southwestern United States.

Just now, WxUSAF said:

12z GEFS looks pretty good. Ridging back along the west coast of Canada by the end, but will take some time to flush out the puke.

Thanks.  Seems like puke in is faster than puke out.

Can't check ensembles.  Anyone know if anymore hints of AK vortex retrograding?

Big thunder in Wilson.  0.48" so far.

43 minutes ago, CAPE said:

The transition to a better longwave pattern does show up towards day 15 on the current ens runs as the AK vortex retrogrades. Latest GEFSx  continues with the progression: by the second week in Jan we have a negative EPO/WPO, neutral PNA, and neutral/slightly neg AO/NAO.
 

 

Hopefully the EPO can help replenish the cold air scoured out by the Pac Puke.

36 minutes ago, Terpeast said:

Much better look, especially for January. Now let’s hope this isn’t underestimating the WAR. 

Consult @Ralph Wiggum for info.  He is the WAR Whisperer.

Alright.  Seems like there is really only one thing to talk about in this thread at the moment: when/if the big AK vortex breaks down/moves.  Some of the more level-headed folks have voiced cautious optimism that it may not be excessively long.  In between waring with the NE Snow weenies Eric Webber mentioned that he is optimistic because intense waves such as that retrograde due to the "beta effect" whatever that is.  So perhaps we have a shot.

2 minutes ago, psuhoffman said:

I agree with @CAPE that our next mModoki Nino is a great test case. We underperformed our last Nino. The excuses have some validity. But if we underperform the next one…it’s starts getting harder to ignore the obvious. If we get a modoki next year and DC gets 40” then maybe it’s been more a temporary cycle. I think it’s part both. Maybe 70/30 bad pattern cycle v climate.  This would have been a bad period in any decade given the pac longwave pattern. But I think it’s been made worse. I’m curious myself to see how “muted” our snowfall is once we get a truly good and long term sustained pattern where we can’t make any excuses if it fails to produce prolific snowfall. 

I know that many gave speculated about next year being a Nino.  Has anyone come across any reason to believe it would be a Modoki?

1 minute ago, brooklynwx99 said:

I think we've just been in a persistent -ENSO base state. this should change once we head into a Nino state, which should occur next year, definitely the year after

Eh, 2018-19 was a Nino though.  Wouldn't have known from the mid latitude response though.  MJO raged into the usual phases.

1 minute ago, psuhoffman said:

Just to drive home the point. This was a previous atrocious period from the 70s. Look at where the negative anomaly is centered!  We would absolutely torch in that pattern today with a severely negative PNA and positive AO/NAO. Yet by todays climo (it’s using 1991-2020) all that produced was “avg” h5 heights in the east!  Do you have any doubts that today a repeat of that longwave pattern would have reds that would make Satin blush all over the east!  

Forgot the picture.

Actually its probably happened multiple years lately.

1 minute ago, Maestrobjwa said:

Wasn't that just 2020-21? The year the PV went down to frickin' Texas and left us on the warm side while they snowed? Lol

It was 2018-19.  I remember a BobChill post from early January about how sickening it was to see that track lead to a rain storm.

2 minutes ago, psuhoffman said:

But I think the atrocious results are a mix of not so good pattern base state AND…ya know

No help can be expected from the MJO.  Per the latest CPC briefing the most likely prognosis is convection will ramp up in the Maritime Continent that we all know and love so well.  I'd love to see a time series of the MJO for the last 5 winters.  Probably hasn't spent more than two weeks in phases 1-2 in that entire span.

40 minutes ago, mattie g said:

Because you seem a good kid, I’ll indulge…

The issue with that post is that the graph shows extreme temp drop events happening regularly over the last nearly 100 years. In fact, the modeled event is less “impressive” than each of those top 10. Attributing this event to climate change in any way misses the point entirely…and does climate change science a disservice, in my opinion.

I may not disagree that climate change is simplifying/could amplify extreme events, but this event is not one of those.

Well said.