Predictions 11-13th July Upper Cut Off

Discussion in 'Alpine & Snow' started by POW_hungry, Jul 4, 2020.

  1. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    Some agreement between GFS & EC, both signall a decent chance at a winter system for the SE in this date range.
    GFS Long Wave plots suggest there may be back to back systems, where as EC bids on a cut-off scenario.

    GFS
    [​IMG]

    EC showing an abundance of cold air. With a broad-based UL trough forming East of Tas. This cut off scenario would suggest low level snowfall (snow to ~600m in Vic) and some snow in strange places. Upper level vort looks like a fair-old upper cut IMO.

    In this scenario we want to hope that lows sits on the MR and rotates.


     
  2. teleroo

    teleroo Lincoln Turns at the Pass Ski Pass: Gold

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    Apologies I know I asked before, but what do the vorticity maps indicate? I'm guessing we are looking for high vorticity values indicating a "tightly wound" low pressure system?? More intense low = higher vorticity = more precip = more snow, assuming there is enough cold??
     
  3. stormkite2000

    stormkite2000 One of Us

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    looking good forecast from the aao. Myself i don't bother with the GFS deterministic for aao. Just look @ it's ens and its in neg values @ this range..
     
  4. doogasnow

    doogasnow One of Us

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    Be good if similar forecasts are still showing up once where 3-4 days out. Lids on for a little longer
     
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  5. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    At upper level it’s the Hallmark of a mature cold core low. Vital signs of the low’s upper-level instability that translate to a unstable airmass, which in turn aid convection and frequent heavy precip.
    I like to think of vorticity as the ‘tree shaking’ action of instab.
     
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  6. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    One hit wonder on EC:


    Whilst GFS holds steady with a trending cold winter frontal system.
     
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  7. snowgum

    snowgum One of Us Ski Pass: Gold

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    ‘Potential for goodness’ perhaps?
     
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  8. Ijay

    Ijay Hard Yards Ski Pass: Silver

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    Must
    Must say i like that chart, potential for some long overdue rain for us on the far south coast. A slow drift to the NE perhaps.
     
  9. stormkite2000

    stormkite2000 One of Us

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    As pow hinted. 12z nowhere near as good as the 00z. That said there would be plenty of weather in the bands for the se if this played out @ the date. Watching.





     
  10. mick chopps

    mick chopps Pool Room Ski Pass: Gold

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    Season starter up high. Wash out everything else?
     
  11. BlueHue

    BlueHue One of Us Ski Pass: Gold

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    Yeh that scenario looks like a knifes edge to me. I'd be a little nervous if that played out, more so if a Vic skier. Potential for a significant base builder though.
     
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  12. stormkite2000

    stormkite2000 One of Us

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    GFS18z was a strong cold front tickling upto the rock.
    [​IMG]


    18z full run all the hallmarks of neg aao should look like.
     
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  13. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    Models have nil alignment other than there's a signal present.
    Needs to verify a few major anoms in our region over the next day or two IMO. Until then it's all speculative from the models POV.
     
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  14. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    Lets not forget this is where EC ensembles puts it's money ATM.
    Rogue, but it's big.


     
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  15. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    Really gotta keep an eye on that deepening low SW of WA today/tomorrow. That's not set in stone yet.
    How that progresses through the bight will determine the path of least resistance for this date range.
     
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  16. Kelpieboy

    Kelpieboy One of Us Ski Pass: Silver

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    Just love these knife edge jobs ,they give the best rollercoaster rides. I got a gut feeling this one will be ok though or at the very least not a negative result.
     
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  17. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    The return of a favourable outcome on GFS 00z run this arvo. Nice slingshot of a trailing low.
    It's so close to cutting off in the bight, on approach though.

    Forgeddabout anything past >160 hours on this run IMO.
    [​IMG]
    [​IMG]
     
  18. Fast Eddie

    Fast Eddie One of Us

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    Yeah looks good after a bit of prefrontal from the NW. Hopefully the other models follow suit and a positive trend continues
     
  19. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    EC going for a craddled cut-off. Not looking great.
    [​IMG]
     
  20. Jasper Schwarz

    Jasper Schwarz One of Us Ski Pass: Silver

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    This says “extended prefrontal” right?
     
  21. stormkite2000

    stormkite2000 One of Us

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    [​IMG]

    [​IMG]

    [​IMG]



    not buying into the ec @all myself atm.
     
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  22. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    Yeah EC seems to be the outlier, I agree.
    The deterministic model seems hell-bent on throwing tributes to it's ensembles trend of a few days ago.
     
  23. Donzah

    Donzah Old n' Crusty Ski Pass: Gold

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    I blame brexit
     
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  24. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    Funny you say that because the Brits back the yank, naturally.
    [​IMG]
     
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  25. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    ICON backs EC so there's that...
     
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  26. Jellybeans

    Jellybeans not woke enough Ski Pass: Gold

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    Gfs got a similar vibe if a little stronger to the system just past IMO.
    Until it pushes further north later on the 12th ofc.
     
  27. stormkite2000

    stormkite2000 One of Us

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    ENS 00z runs cmc ens looks anvil shape its likely see'n a ridge.
     
  28. Jellybeans

    Jellybeans not woke enough Ski Pass: Gold

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    Right in the middle of two LWTs....

    EC ensemble mean with that stupid yucky setup again:
     
  29. Kletterer

    Kletterer Thredbo Doughnut Tragic Moderator

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    Not buying it.
     
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  30. stormkite2000

    stormkite2000 One of Us

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    Yeah Kletterer very suss the ec. It shifted from centering over se vic on the 00z 4th run. To centering on the nw nsw border on the 5th. Must be like a 1000 klm's shift nw in one full cycle.
     
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  31. Donzah

    Donzah Old n' Crusty Ski Pass: Gold

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    Bowl of spaghetti says cutoff cradle.
    With minimal confidence
     
  32. stormkite2000

    stormkite2000 One of Us

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    Could only get to 120hrs with icon 006z latest. its much further sw than the ec .You can see there is quite a difference with the 00z ec @ that time.



     
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  33. Gregah

    Gregah One of Us Ski Pass: Gold

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    A good lick of moisture on 06z GFS at both the front and back ends of this system. Depending on if / where that Bass Straight low forms things could get interesting.

     
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  34. Donzah

    Donzah Old n' Crusty Ski Pass: Gold

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    Never in my life have I wanted a yank more.

    The French Canadian that time.. Purr
     
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  35. stormkite2000

    stormkite2000 One of Us

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    00z GFS got 00z cmc ens compressed look under the ridge.





     
  36. Donzah

    Donzah Old n' Crusty Ski Pass: Gold

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    That looks ideal
     
  37. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    Some clear distinction between pineapple and polar/mid-lat moisture on GFS:
     
  38. Donzah

    Donzah Old n' Crusty Ski Pass: Gold

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    For the record.
    Having been a punter re weather for 30 years.
    I've never seen a prog or outcome like EC has offered come to fruition.
     
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  39. MisterMxyzptlk

    MisterMxyzptlk Old n' Crusty Ski Pass: Gold

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    I was just going to post this
    Nor have I ever seen an inland cut-off low deliver snow in any great quantity to the fields
    But fingers crossed!
     
  40. stormkite2000

    stormkite2000 One of Us

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    EC 12z. has got the cold air back in se



     
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  41. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    Synoptically a messy one on EC, this morning.
    Can’t but help think this one will fade to black and clear some ridge for the 18-20th system (BBQ thread).
    This one sits between LW troughs so it’ll be flukey at best IMO.
    ICON, the Canuck all a bit loose on it this morning.
     
  42. Jellybeans

    Jellybeans not woke enough Ski Pass: Gold

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    Yeah it ha seemed to have a weird vibe from the get go, with the weird progs, per the lack of LWT support.
     
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  43. Donzah

    Donzah Old n' Crusty Ski Pass: Gold

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    Icon 18z and GFS18z have some promise
     
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  44. Donzah

    Donzah Old n' Crusty Ski Pass: Gold

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    More love from Ncep as well
     
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  45. POW_hungry

    POW_hungry Old n' Crusty Moderator Ski Pass: Gold

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    Yeah, looks to carry more East than meridonal. Much better.
     
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  46. stormkite2000

    stormkite2000 One of Us

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    [​IMG]

    Tricky one atm just how i like em.
     
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  47. mick chopps

    mick chopps Pool Room Ski Pass: Gold

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    Oh hi NZ.....
     
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  48. stormkite2000

    stormkite2000 One of Us

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    Yeah not to much wrong with it.



    Pretty much inline with nasa's guidance.



    The axis on the trough looks much sharper than was being shown on eps.








     
    #48 stormkite2000, Jul 6, 2020
    Last edited: Jul 6, 2020
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  49. snowgum

    snowgum One of Us Ski Pass: Gold

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    I note That a lot of these models struggle to predict snow for the smaller and more southern Vic hills.

    For this one, it could be because it’s going to to be too warm and hence clear precipitation. Or perhaps these hills are too low and the actual snow area too small to show up on a broad scale model.

    Either way, even when ‘we’ see a nice dump at Lake Mtn, Baw Baw, Snowy Range/Reynard etc... it’s often overlooked by the models IMO and not predicted.

    Happy to be told I’m wrong by the experts - interesting to share an Observation of forecasts.o_O
     
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  50. mick chopps

    mick chopps Pool Room Ski Pass: Gold

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    this does not spell snow for Baw Baw.