• Hello, please take a minute to check out our awesome content, contributed by the wonderful members of our community. We hope you'll add your own thoughts and opinions by making a free account!

Pattern The Great December Dump

GaWx said:
We already know it has a +PNA/-EPO bias. So, what you’re showing happens quite often with the GEFS. Nothing new here and it says practically nothing about how January will be other than it likely being mild the first few days.
Click to expand...

In this particular case, I think this is related to the GEFS progressive bias w/ convectively coupled kelvin waves and the MJO in the Pacific & Western Hemisphere. The hemispheric z500 forecast anomaly trend throughout most of the period closely resembles MJO phase 6 in Dec during +ENSO.

nino_6_dic_mid.png

gfs-ens_z500trend_namer_26.png
 
Webberweather53 said:
In this particular case, I think this is related to the GEFS progressive bias w/ convectively coupled kelvin waves and the MJO in the Pacific & Western Hemisphere. The hemispheric z500 forecast anomaly trend throughout most of the period closely resembles MJO phase 6 in Dec during +ENSO.

View attachment 28573

View attachment 28572
Click to expand...


On the other hand this 500mb pattern will greatly increase WAFz onto the polar vortex because it projects onto the standing planetary waves.
 
Webberweather53 said:
On the other hand this 500mb pattern will greatly increase WAFz onto the polar vortex because it projects onto the standing planetary waves.
Click to expand...
Isotherm has been dead on so far with his interpretation. He is giving optimism if the qbo reverses negative by February. Imo, the AAM resembles a niña, which the pattern resembles moving forward. With all that said, lets go golfing!!!
 
Mr. Golf said:
Isotherm has been dead on so far with his interpretation. He is giving optimism if the qbo reverses negative by February. Imo, the AAM resembles a niña, which the pattern resembles moving forward. With all that said, lets go golfing!!!
Click to expand...

No.

The pattern going forward does not in any way shape or form resemble La Nina at a hemispheric scale esp with a deep Aleutian vortex & persistent SE Canada ridge. The -PNA is being induced by West-central Pacific convection that's reinforced by the already +ENSO base.

The appearance of a -PNA doesn't automatically mean said pattern is La Nina like. As for the -AAM, it was largely being created by +IOD which also is not consistent w/ La Nina. The upper level divergent circulation anomalies globally are also as far as they could be from resembling a La Nina & so are the corresponding SSTAs. There's nothing La Nina about this
 
Webberweather53 said:
No.

The pattern going forward does not in any way shape or form resemble La Nina at a hemispheric scale esp with a deep Aleutian vortex & persistent SE Canada ridge. The -PNA is being induced by West-central Pacific convection that's reinforced by the already +ENSO base.

The appearance of a -PNA doesn't automatically mean said pattern is La Nina like. As for the -AAM, it was largely being created by +IOD which also is not consistent w/ La Nina. The upper level divergent circulation anomalies globally are also as far as they could be from resembling a La Nina & so are the corresponding SSTAs. There's nothing La Nina about this
Click to expand...

And besides, the AAM is forecasted by the EPS to go positive for at least a week starting ~12/25 for the first time since June,
 
Mr. Golf said:
Isotherm has been dead on so far with his interpretation. He is giving optimism if the qbo reverses negative by February. Imo, the AAM resembles a niña, which the pattern resembles moving forward. With all that said, lets go golfing!!!
Click to expand...
Webb knows his stuff and if you are new welcome, and we all learn from him
 
Wish this look was valid for December 4th rather than January 4th. Without going down to Joe's Index Shop and pulling a 3 letter combo off the shelf, I'll suggest that whatever the state of the tropics or polar regions, we look to continue our streak of AN Decembers and rough starts to January. Hopefully, it turns around before mid-month. But if this pattern plays out, it might take a while. Good thing is, I guess it's almost as bad as it will hopefully get this winter.

gfs-ens_z500_mslp_namer_65.png
 
accu35 said:
Webb knows his stuff and if you are new welcome, and we all learn from him
Click to expand...

@Mr. Golf is a longtime member here but his name has changed slightly.

Meanwhile, the 12Z Euro maintains SE warmth on and after 12/23. Absolutely nothing new about this.
 
While many folks are complaining and crying about the mild 12Z GEFS, the 12Z EPS comes in colder than the 0Z EPS and much colder than the 12Z GEFS during the 11-15 day period. Instead of the 12Z GEFS torch, the 12Z EPS has near normal temps in the first few days of Jan. Say what?
 
GaWx said:
12Z EPS 360 hour vs 12Z GEFS 360:

EPS: near normal/NO torch/wet
View attachment 28578

GEFS:
View attachment 28579
Click to expand...

Thanks for posting these. For actual temps, agreed that it doesn't look torchy. I think many people are looking forward to a cold pattern with some chances to see snow. The actual features of both of those maps still kind of suck. Need the PV to drop SE and not park it way up north as well as better ridging out west. Those things probably work in tandem. The Euro is definitely better from a sensible weather standpoint, but there's not really a way to polish that turd pattern that both images allude to.

It's hard to know how the Euro is evolving toward the end, though. Maybe, it's reshuffling things favorably? Hopefully, that is the case. Either way, thanks for posting it!
 
Rain Cold said:
Thanks for posting these. For actual temps, agreed that it doesn't look torchy. I think many people are looking forward to a cold pattern with some chances to see snow. The actual features of both of those maps still kind of suck. Need the PV to drop SE and not park it way up north as well as better ridging out west. Those things probably work in tandem. The Euro is definitely better from a sensible weather standpoint, but there's not really a way to polish that turd pattern that both images allude to.

It's hard to know how the Euro is evolving toward the end, though. Maybe, it's reshuffling things favorably? Hopefully, that is the case. Either way, thanks for posting it!
Click to expand...

Baby steps!
If the Bleaklies were based on the 12Z, we'd know where this EPS were heading. But unfortunately, they're based on 0Z. So, there MAY bet a lot of bleakness this evening. But keep in mind that even if bleak, they might have looked better had they run based on 12Z. :):)

But I still wonder if they'll be bleak as they were pretty decent on the Monday run for early to mid Jan.
 
Rain Cold said:
Thanks for posting these. For actual temps, agreed that it doesn't look torchy. I think many people are looking forward to a cold pattern with some chances to see snow. The actual features of both of those maps still kind of suck. Need the PV to drop SE and not park it way up north as well as better ridging out west. Those things probably work in tandem. The Euro is definitely better from a sensible weather standpoint, but there's not really a way to polish that turd pattern that both images allude to.

It's hard to know how the Euro is evolving toward the end, though. Maybe, it's reshuffling things favorably? Hopefully, that is the case. Either way, thanks for posting it!
Click to expand...

Days 10-15
db7b11e6ee45c74d7b2b8cc257a837c0.gif



Sent from my iPhone using Tapatalk
 
whatalife said:
Days 10-15
db7b11e6ee45c74d7b2b8cc257a837c0.gif
Click to expand...

Thanks for posting, It is never a bad thing to have 500 mb hts below normal. And even the GEFS runs prior to 12Z still didn't have below normal 500 mb hts in the SE. These below normal heights that are lower than those of the N US resemble El Nino pattern.
 
Rain Cold said:
Things seem to stay put as they get muted, presumably due to smoothing.
Click to expand...

That is the problem with the GEFS and it’s entire run SW trough. It’s clear it doesn’t know what to show even at 252hrs due to timing issues.
 

Attachments

  • 96B63E1F-192F-4D1E-8305-F2FCC6B80865.png
    96B63E1F-192F-4D1E-8305-F2FCC6B80865.png
    117 KB · Views: 27
You must log in or register to reply here.
Back
Top