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KyleHenry

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Posts posted by KyleHenry

  1. 25 minutes ago, bluearmy said:

    I think the eps clusters will have some stonkers 

    For what it’s worth, final confirmation has to be sealed by the 150hPa otherwise HP will never hold in place. What do you know? it does this time. 
     

    If TPV vacates east Asia and turns slack in that area then this episode will be colossal in terms of cold/snow but also brutal.

     

    IMG_7176.thumb.jpeg.f21aabcb8f75d46a16b32c4916e76257.jpeg

    • Like 6
  2. 21 minutes ago, AO- said:

    Good evening all,

    Does Anyone know what "is wrong" with the GFS operational?  It has been leaving the "bunch"  for three runs in a row now. It is clearly (again) an outlier. Synoptically it is on its own for quite a while now. 

    gfs-leeuwarden-knmi-nl-5.jpeg

    I believe that the GFS is reflecting its observations on the SPV’s return to the default position, after current displacement. Therefore it has a habit of speed running the modelling dynamics.

    IMG_7174.thumb.png.a371fb9491a24c19372ce27d0808cc9c.png
    At 144z it predicts the TPV to move 80% into Newfoundland and 20% into Kara sea. Not only that it has multiple LP spawning off Greenland in a highly condensed area. 
     

    IMG_7173.thumb.gif.e0064466619f2659da66d49bea081e1c.gif

    UKMO has the TPV split 50/50, less congested with slacker upper air. Anyway we will remember this moment in a weeks time and decide how correct the GFS was/ wasn’t l.

    • Like 3
  3. 3 minutes ago, bluearmy said:

    Going to be an interesting cross sectional to look at from that gfs run 

    is that monster Arctic high a straight downwell of the reversal or does it come from trop influence ?

    Both but by a different mechanism,the PV displacement (SSW or close to reversal) permits the Arctic high to form by moving the PV off the default position.  The Aleutian low creates the brake for the WAA from the Pacific into the Arctic circle. Then the Arctic High is allowed to fill the vacant space. PV needs to reverse for the Trop AH to gain height in the target zone.

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  4. There were hints that the TPV could fall entirely into Europe. Which would be an atomic hit of cold air if that occurred. I remain hesitant on that outcome for now.

    Whereas normally 70/30 and the seventy going into North America.

    Anyway the movement of the TPV is still to be resolved but the predicted timing 9/10th  Jan for UK cold/snow prospects still holds for now.  
     

    IMG_7171.thumb.png.23c209d2d8df667da0b44011cadd04ab.pngIMG_7170.thumb.png.480d07428258c2ede75be6830b352b25.png

     

    The TPV pattern is there on both models, which would align with -40C expectations for Scandinavia. 

    • Like 2
  5. 8 minutes ago, bluearmy said:

    Ec day 10 fully in line with gefs and eps at the same timescale - will assume the 12z eps won’t go astray in twenty mins 

    Fully admit that’s surprising given the expected uncertainty 

    Very surprising.IMG_7166.thumb.jpeg.c9bd4edb6fa6d855e43aec6d1e562411.jpeg

    I was looking at this. It’s a pivot point as to how the TPV NE Canada will dissolve in terms of where and how much the cold air will move to. 

    • Like 1
  6. 9 minutes ago, Big Gally said:

    Judah cohen blog worth a read. He mentions the cold weather spreading to the UK next week. I hope further into January we will see a change. 

    I can see his reasoning. IMG_7158.thumb.jpeg.7ccc83ce9d539eecb207d4e9e1c4e81c.jpeg

    Yes it 240z but it’s based on pattern recognition of PV displacement. Red arrows indicate expected movement for approximately 9th Jan. HP up into Greenland and TPV dropping into US and Western Europe. So it’s all eyes on UKMO and ECM next two days for confirmation.

    • Like 4
  7. 3 minutes ago, bluearmy said:

    The gefs 06z are another step away from where they were 24 hours ago 

    but atm, they don’t have support from eps and geps 

    I would add that the eps and gem members have not shown an obvious clustering to tremendously wintry output - however, the eps clusters in the extended as posted by Mike are majority positive for cold and this isn’t a flip from the eps (which sometimes happens and is unreliable when it does)

    Blue what’s the EC46 showing for around the 13th Jan at 10hPa?

  8. 2 minutes ago, northwestsnow said:

    Interesting.. 

    We seem to be seeing a reasonable amplitude  mjo phase 1 incoming too,although I confess my understanding is limited ..

    Pacific Ocean is the source driver. Westerly wind burst towards Indian Ocean. Kinetic energy goes up high in atmosphere to create the EAMT event if the timing is right which leads to warming in stratosphere. Then it must dominate the PV and reverse the air flow.

    Results in PV displaced and allows a -AO which is HP Arctic circle. Creates the braking system to allow High latitude blocking. Simple heh! 

     

    • Like 7
  9. 16 minutes ago, northwestsnow said:

    I guess the lack of comments says it all.

    Thin gruel.

    Understandable if just following the daily model runs and awaiting a significant change to happen. 
    The problem being, it’s just too early and can only lead to teeth gnashing.

    IMG_7144.thumb.png.5a692143c698872ba7743a936174e0b6.png

    What is the time line for potential change?

    Stratospheric warming process begins 31st December. 
     

    IMG_7143.thumb.jpeg.d47c795eeb804c9bd71e2ecd3f73ba3c.jpeg

    Expect around 3rd/4th Jan for strong -AO to form and take position over the Arctic circle. 
     

    The pattern is always the same, Cold Asia. Cross polar flow to create cold North America. Estimated to be around 5th Jan.

    Then Europe approximately 5-8 days later. -NAO. With high pressure into Greenland.

    None of this occurs without the SSW. It is still too early to say exact details of a major event. I’m 75% certain it will be, by slightly dipping below 0m/s at 60N. 
     

     

    • Like 7
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  10. And so it begins, repeated evolution of Aleutian LP systems, how many and for how long matters in terms of creating enough dampening to allow HLB to develop. Estimate to be 14-17th January.
     

    This winter seasons pattern has been a repeat and rinse pattern. No coupling between TPV and SPV, therefore both have been allowed to act independently of each other. 
     

    If no coupling occurs after this event then a repeat in this process will occur again in late February.

    Like mid November 2022, the Aleutian LP created the breathing space for HLB between Greenland to Scandinavia. The models pushed for Scandi HP and an easterly when the result matched the anomaly chart predictions of Greenland HP.

    It is this process of Aleutian LP and Scandi HP which is the base foundation of a possible SSW
     

    Attaining a SSW this winter doesn’t matter due to there being minuscule coupling all season. 
     

    Next year 23/24 it will matter with El Niño emerging.

    GFS picked the signal and showed Easterly. Time to focus on ECMWF. Stall of Aleutian LP systems does point towards Greenland HP again. NW Europe cold again by the 17-24th Jan. US to follow from the beginning of February. ( NW Europe could hold pattern for 2-3 weeks again similar to early December.

     

    Could contain: Plot, Chart, Outdoors, Nature, Art

     

     


    Original post: https://community.netweather.tv/topic/98196-model-output-discussion-new-year-and-beyond/?do=findComment&comment=4783027
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  11. 32 minutes ago, goosey007 said:

    surely if ECM has called this wrong is deserves a relegation to the championship in these type scenarios moving forward and we promote the GEM to the premier league for calling cold with greenland block ...we already know ICON is sunday league lol

    Just discovered yourself a bias flaw in the ECM for future scenarios similar to now.

    GFS picks up signal early but fails in its timing of the event, this time it has dealt with the block and slow moving low pressures off Greenland much better than ECM
     

    ECM is stronger regarding a faster evolution of the WAA into Greenland and struggles with the slower evolution. 
     

    UKM plays a tighter time game,hence more reliable.

    • Like 1
  12. 13 minutes ago, IDO said:

    So the gfs op 12z was a signature run?

    >>>anim_tvz7.gif

    If that is the case, def a period of unsettled weather for the UK up to and beyond d16; so end of month for the blocks to settle and maybe an Atlantic ridge for our sector and hopefully not too west based? The Pacific ridge seems more Alaska based on this suite, a recurring theme this winter?

    The mean...

    anim_irq6.gif

    ...shows a similar pattern as you suggest but for obvious reasons not so well defined. That does suggest the transitory phase will not be blocked, so normal UK Jan flow?

    Observe the pattern, three TPV lobes are forming. SSW will disintegrate TPV to mid latitudes. One will be for Europe, question is how far west it can move.

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  13. For those that care to know, this post is for you.
    The Tropospheric Polar Vortex is a maelstrom, hence the difficulty for models to forecast the precise mapping of it’s movements. 
     

    Therefore during SSW events you’ve got to look higher up in the atmosphere, when there you’ve got to watch for the formation of -AO in the Polar region.

    ECMWF 240z from Berlin at 100hPa has the -AO form on the Northern Pacific side of NH

    FE6D0403-479F-4C16-A5DD-0439AED1DE2E.thumb.png.0c99a3ff2659b48055c7bb299b9762a8.png

     

    The GFS excels at picking up the pattern at range and predicts the TPV bleed across Polar region. This brings the Northern US back into winter proper.

    The GFS’s flaw exist in timings of the exact movement. 
    Whereas the ECMWF runs approximately 3 days behind the GFS before it nails the exact movements of TPV and the GFS flounders.

    2AD38C66-08F7-4EC6-AB01-C9692190BDB6.thumb.png.4c61a73bf1ae8e05cf5c7fda0fd81f5c.png7579D56B-A285-4348-B17C-FFA6584AD7B0.thumb.png.f8b7bd5039af80cb465b0b6a0a34297f.png

    All I’ll say now is watch for TPV transfer from East Asia into N. America. WWA up via Pacific to form -AO. What happens afterwards can be deciphered by each others level of understanding.

    • Like 7
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  14. 2 minutes ago, Steve Murr said:

    Yes just saw this & if you look at 144 chart plenty of cold to tap just to the North...

    CWB to curve up to Greenland and back towards the eastern US. The lack of TPV and energy contained inside the wave break on the UKMO 168z. HP may not hold for long over Greenland but cold air down through the UK and retrogression of HP towards Scandi a likely outcome. 

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